sellecting valve springs, and setting up the valve train



sellecting valve springs, and setting up the valve train

Postby grumpyvette » September 20th, 2008, 2:16 pm

How do you determine the spring pressure needed to keep the valves under control for a given lift, duration, and max rpm.
It might take you several hours to read thru all the links and sub links but its time very well spent as it could save your engine from destruction and save you thousands of dollars
youll want some tools, naturally the amount of info you need and how precisely youll want to control your valve train will effect the tools and info required and to some extent the higher the rpm levels the higher the cost of tools and components required will be, for a basic street small block a black magic marker and a feeler gauge, and adjustable length push-rod and a geometry check tool can give you the basic info required
these tools come in different designs but youll want ones matching your application, in many cases the cam manufacturers and cylinder head manufacturers can give you a great deal of good info on common applications ,clearances and spring load rates and valve train geometry required

Recommended Valve Spring Pressures
ID STRONGLY SUGGEST THIS READING ASSIGNMENT
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preventing cam & lifter break-in failures


it should be rather obvious that there's options,you'll chose in both valve train components and lubricants, cam failures are usually the result of incorrect CLEARANCES or too much SPRING PRESSURE or LACK of ADEQUATE LUBRICATION,USE DECENT MOLY CAM LUBE, and decent quality oil, adding MAGNETS to trap metallic CRUD HELPS, if your not getting constant oil flow from each rocker /push rod at idle theres something wrong and that needs to be checked

http://www.youtube.com/watch?v=wzKtaDke22k
http://cranecams.com/userfiles/file/334-343.pdf

http://www.woodcarbs.com/valvesprings.htm

http://www.jesel.com/valvetrain/index.p ... rs/tie-bar

https://sdparts.com/details/scoggin-dic ... ter/sd1005

viewtopic.php?f=52&t=9687&p=48105#p48105

http://www.usaperform.com/documents/Spe ... 0Chart.pdf

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Please note, the valve spring pressure figures given here are guidelines only. Some special applications may require different pressures. When in doubt, please contact your camshaft supplier.
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If your not getting oil flow, at the rockers,youll still need to verify the oil feed holes line up and are not blocked and the rockers adjusted correctly, try backing off on the adjustment nut as the engine idles to the point the rocker clicks noticeably then slowly tighten just to the point the noise stops , then add only a 1/4 turn, and see if that doesn,t cure the oil feed issue
this is what ERSON CAMS SUGGESTS AND MOST COMPANY'S
HAVE VERY SIMILAR PRESSURE SUGGESTIONS


roller lifters are generally heavier than flat tappet lifters and roller cams tend to have more aggressive ramp speeds requiring stiffer valve spring load rates
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The following recommendations are from Erson Cams. If you have questions, you can reach their tech department at 800-641-7920.

Hydraulic Flat Tappet Camshaft: 110 lbs Seat pressure/250-280 lbs open pressure

Solid Flat Tappet Camshaft: 130 lbs Seat Pressure/300-325 lbs open pressure

Hydraulic Roller Camshaft: 130-140 lbs Seat Pressure/300- 355 lbs open pressure

Solid Roller Camshaft: (Minimum Safe Pressures DEPEND ON SEVERAL FACTORS)

Up to .600˝ valve lift: 200-235 lbs Seat Pressure/600 lbs open pressure

Over .600˝ valve lift: 250-280 lbs Seat pressure /100 lbs pressure for every .100˝ of valve lift


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CAST CAM CORES ARE NOT DESIGNED TO HANDLE OVER ABOUT 130lbs SEAT and 400lbs OPEN SPRING LOADS YOU NEED A BILLET CAM CORE FOR DURABILITY IF THOSE LIMITS ARE EXCEEDED

typically chevy valve springs use single or dual valve springs usually with an inner friction damper
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single valve spring with friction damper
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dual valve springs with friction damper
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dual valve springs without damper

you must check EVERY ENGINE you assemble,or change valve train components on, for valve spring coil bind, on all springs and dampers,retainer to valve guide clearance,rocker to retained edge clearance, rocker slot to rocker stud clearance,the correct centered rocker to valve tip geometry , piston to valve clearance,push-rod to push-rod guide alignment and clearance , the heads for clearances and a dozen other factors listed below over the whole 720 degree repetitive cycle the valve train cycles thru
obviously you need to verify all valve train clearances and prevent parts binding at any point in the 720 degree repeat cycle the valve train operates in and you need to try to maintain almost all valve train geometry to minimize side loads on valve stems in guides to reduce wear and friction, and keep the lubricant flowing to absorb and remove heat from the valve train components

http://www.summitracing.com/parts/PRO-66789/
http://www.summitracing.com/search/Part ... -Checkers/
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viewtopic.php?f=52&t=5931&p=18267#p18267

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http://www.northernautoparts.com/Produc ... ductId=678

viewtopic.php?f=52&t=788

viewtopic.php?f=52&t=9687&p=36006#p36006

http://www.psisprings.com/index.php?opt ... view&id=17

http://www.cvproducts.com/Products/Engi ... %20Spring/

WATCH THE VIDEOS, READ THE LINKS
http://www.youtube.com/watch?v=qw5PWiOwXhI

http://www.youtube.com/watch?v=Cqx8Cs6O ... re=related

http://www.youtube.com/watch?v=5GBNLlsi ... re=related


IT WILL HELP A great deal if you,READ THRU THE LINKS AND SUB LINKS
viewtopic.php?f=52&t=1376

viewtopic.php?f=54&t=2187

http://www.supercarsunlimited.com/info/ ... prings.htm

http://www.compcams.com/Products/CC-%27 ... %27-0.aspx

viewtopic.php?f=52&t=399

http://www.hotrod.com/techarticles/engi ... ewall.html

viewtopic.php?f=52&t=3124

viewtopic.php?f=52&t=3009

http://www.youtube.com/watch?v=o5is9BsH5OU

viewtopic.php?f=52&t=689

viewtopic.php?f=52&t=9392

viewtopic.php?f=52&t=2632

viewtopic.php?f=52&t=1719

http://www.summitracing.com/parts/cca-7 ... dia/images

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a good set of big block chevy push rods can easily cost over $200-$300

READ THIS THREAD
viewtopic.php?f=52&t=6491&p=20681&hilit=spray+springs+cooling#p20681

http://www.hotrod.com/techarticles/engi ... vesprings/

viewtopic.php?f=52&t=1489

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Proper push rod length is absolutely critical for peak performance—minimizing bent or broken valve stems, guide wear, and energy-wasting valve side-loading friction.
With the lifter located on the round base circle, position the Push Rod length Checker (make sure you have the Checker with the proper diameter hole) over the stud. Ideally the Checker should contact the top of the push rod and the valve tip evenly at the same moment, should the Checker contact the push rod first, measure the gap between the front of the checker and the valve tip, and purchase a shorter push rod of the correct length. Should the Checker contact the valve tip first, measure the gap between the back of the Checker and the top of the push rod, and purchase a longer push rod


viewtopic.php?f=52&t=2091

viewtopic.php?f=44&t=2839&p=12739#p12739

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viewtopic.php?f=52&t=196

http://www.racingsprings.com/
[b](866) 799-9417

http://www.racingsprings.com/Staff
heres their ph#
Toll Free (866) 799-9417
I always just order the springs retainers valve locks and spring seats as a package deal (NOT CHEAP BUT EVERYTHING WORKS AND FITS) then you just need shims under the valve spring seats occasionally to get the correct installed height

http://www.racingsprings.com/Valve%20Springs/Store/13[/b]

http://store.procompelectronics.com/p-1 ... of-16.aspx
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I buy most of the valve springs I use from these guys, if you tell them EXACTLY what you are doing , clearances, cam, spring diam, length etc. they can suggest something that fits your application almost EXACTLY, they are usually very helpful


I usually buy valve springs from these guys

http://www.racingsprings.com/Store/ProductCategory.asp?ProductCategoryID=13

if your not sure what you need in load rates and clearance and installed height,ETC., ask the tech guys on both that site and your cam manufacturers site.
in an ideal world the rocker pushes strait down the valve stem center line to reduce friction,but having the rocker wear pattern centered on the valve tip is far LESS important than having it rather narrow indicating less side thrust or drag on the valve
and having the rocker geometry a bit off as long as the clearances are correct, is unlikely to cause noise issues as much as long term valve guide wear issues


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http://www.summitracing.com/parts/CCA-7901-1/
actually measuring clearances helps a great deal

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http://www.summitracing.com/parts/PRO-66832/?rtype=10
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If your not sure about the proper installed spring height,spring load rates,valve shims ,valve spring seat and required clearances,why not have the machine shop suggest what would match your current needs after telling them the clearance requirements and cam lift.
remember longer valves generally require longer push rods and getting the rocker geometry correct is critical to durability, shims & spring seats can easily be used to shorten installed spring heights,they also make .050 off set valve keepers and .050 off set spring retainers so you can adjust installed height over a full .200 with the same valve length

READ THESE

viewtopic.php?f=52&t=1005&p=15534&hilit=spring+shims#p15534

viewtopic.php?f=52&t=697

viewtopic.php?f=52&t=4962&p=13814&hilit=spring+shims#p13814

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heres a printable degree wheel
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INSTALLED SPRING HEIGHT-MINUS SPRING BIND HEIGHT-minus .060 thousands -EQUALS MAX LIFT
http://www.enginebuildermag.com/Article ... _much.aspx

http://www.kennedysdynotune.com/Valve%2 ... 20Tech.htm

viewtopic.php?f=50&t=404&p=496&hilit=rope+adapter#p496

READ THRU THESE INFO LINKS ALSO, THERE A GREAT DEAL OF USEFUL INFO IN THE LINKS, and SUB-LINKS POSTED HERE THAT YOU NEED TO KNOWyes IM sure that appears to be a huge investment in time and effort , but having a durable and stable valve train takes a bit of effort and knowledge to set up correctly, you can rarely just assemble parts and have it work correctly.
If your thinking of running over 450 lbs or valve spring at peak lift Id suggest both 7/16" rocker studs and a stud girdle , be used and if your running 500lbs-600 lbs plus of spring pressure , its pretty much mandatory,on both a sbc and bbc
and Id suggest the STEEL ROLLER ROCKERS,be used rather than aluminum as they have a longer fatigue life, the last thing you want is a rocker stud cracking a head, or a rocker coming apart at high rpms
in theory brass/bronze valve guides are minimally softer and wear faster,than iron valve guides, but in reality if your using the proper valve seals, and have your oil flow to the upper valve train functioning correctly with reasonably clean oil, theres a thin coat of oil between the valve stems and the surface of the inner valve guides, that prevents any wear if your valve train geometry has the main loads centered on the valves center line. keep in mind having proper valve train geometry, and having constant clean oil flowing over and cooling the valve springs, and rockers, plays a huge part in valve wear issues.remember the surface Finnish, clearances, valve seals and oil viscosity along with proper valve train geometry and material used in the valves also effects valve wear
btw coating the valve stems with a mixed slurry of marvel mystery oil and crane cams MOLY assembly lube during the cylinder head assembly process, tends to prevent dry start issues with the guides seizing valve stems

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heres a chart I found that I don,t fully agree with, I think its a bit conservative, by about 3%-5% on the required cam duration ,required to avoid detonation with todays crappy octane fuel, but it at least gives you a base to work from, but Id suggest selecting a bit more duration
YOUR REALLY GOING TO WANT TO READ THRU THESES SUB LINKS FOR MORE COMPLETE INFO

viewtopic.php?f=52&t=528

viewtopic.php?f=52&t=1376

http://www.compcams.com/technical/FAQ/F ... prings.asp

viewtopic.php?f=52&t=6198&p=19404#p19404

http://www.pontiacstreetperformance.com ... ngeom.html

viewtopic.php?f=52&t=2746

http://www.hotrod.com/techarticles/engi ... vesprings/

viewtopic.php?f=52&t=1376&p=3033#p3033

http://www.carcraft.com/techarticles/vo ... index.html

viewtopic.php?f=52&t=3367&p=8900&hilit=rocker+fulcrum#p8900

http://carcraft.automotive.com/9794/vor ... index.html

http://www.supercarsunlimited.com/info/ ... prings.htm

viewtopic.php?f=52&t=2768&p=7190#p7190

http://www.hi-flow.com/HPYT4.htm

viewtopic.php?f=44&t=799

http://www.kmotion.biz/instht.htm

http://www.carcraft.com/techarticles/11 ... index.html

viewtopic.php?f=52&t=401&p=491#p491

http://www.aa1car.com/library/camshafts.htm

viewtopic.php?f=50&t=501

viewtopic.php?f=44&t=1246

viewtopic.php?f=52&t=788

http://www.compcams.com/catalog/COMP201 ... 010_10.pdf

http://www.chevyhiperformance.com/techa ... fters.html

viewtopic.php?f=52&t=324

viewtopic.php?f=52&t=198&p=233&hilit=louis#p233

http://www.ovaltracking.com/tech/2006/i ... ive-3.html

http://www.vetteweb.com/tech/vemp_0204_ ... index.html

viewtopic.php?f=52&t=90

viewtopic.php?f=52&t=1005

viewtopic.php?f=52&t=401&p=7061#p7061

viewtopic.php?f=52&t=410&p=1907#p1907

http://cranecams.com/?show=valveSpringsFAQ

viewtopic.php?f=52&t=126&p=1193&hilit=+girdle#p1193

http://www.compcams.com/Products/335-353.PDF

viewtopic.php?f=52&t=697

viewtopic.php?f=52&t=61

viewtopic.php?f=52&t=126&p=1270&hilit=+roller+rockers#p1270

viewtopic.php?f=52&t=1053

viewtopic.php?f=50&t=10363

http://www.compperformancegroupstores.c ... re_Code=PH

http://www.cranecams.com/?id=5&show=faq

http://www.popularhotrodding.com/tech/0 ... index.html

http://www.corvetteflorida.com/forums/s ... php?t=5725

http://www.circletrack.com/drivetrainte ... index.html

http://www.circletrack.com/enginetech/c ... index.html

http://www.hotrod.com/howto/51058_cylin ... index.html

http://www.flatlanderracing.com/revkitsafr.html

viewtopic.php?f=52&t=8582&p=30180#p30180

http://www.powerperformancenews.com/for ... a-863.html

http://popularhotrodding.automotive.com ... index.html

viewtopic.php?f=52&t=663&p=911&hilit=+girdle#p911

http://www.stockcarracing.com/techartic ... index.html

http://www.supercarsunlimited.com/info/ ... prings.htm

http://www.chevyhiperformance.com/techa ... index.html

http://www.compperformancegroupstores.c ... y_Code=BEE

viewtopic.php?f=52&t=974

viewtopic.php?f=50&t=903

viewtopic.php?f=52&t=399

viewtopic.php?f=52&t=4564&p=12170#p12170

viewtopic.php?f=52&t=663&p=911&hilit=girdle#p911

viewtopic.php?f=51&t=125

viewtopic.php?f=52&t=2875

http://www.popularhotrodding.com/engine ... ables.html

If your rebuilding an engine ,the questions that really should be asked here......
were you completely happy with the old cam or did you feel you wanted more upper or lower rpm band torque, did you like the way the engine ran, or did you feel it needed some tweaking?.....
what would you have liked to be changed about the power band when the old grind was in use?
BTW are you aware that reducing cams lift and valve spring load rates /pressures, and the degree of the aggressive cam ramp acceleration tends to increase durability in valve train components? yes it may cost you some hp, but it may be a good trade for increased durability
thats something thats partly an art, not truly an exact science, due to differences in ramp acceleration rates, lifter design, and valve train geometry, spring load rates,harmonics, etc. I usually contact the cam manufacturer and get their input,, because they are very much interested in having their product perform well. then I carefully verify my combos clearances and spring load rates,(verifying the clearance issues are VERY important) but you need to understand that if you substitute a different brand or style of lifter or rocker,etc. its going to change the results, harmonics and rpm band, generally you can add some stability with a rocker stud girdle, and if you find your having control issues you can usually either add a rev kit or swap to a slightly stronger load rate in a beehive or dual spring.
you might want to look into BEE HIVE VALVE SPRINGS, because, if they are available for your application. they allow both a lighter spring with the same pressures and a smaller diam, and lighter weight retainer , giving greater rocker clearance and lighter inertial loads at high rpm
lower spring pressures usually result in less wear on the valve train, smaller diam. retainers, used on bee hive springs generally allows higher rpms and lower loads on the valve train, IDEALLY, you want the LOWEST spring rates and LIGHTEST valve train components that will still control the valve train in the rpm ranges your engine operates in.:thumbsup:
check with your cam supplier they tend to cost slightly more but they can give you some additional rpm capacity and lower stress
keep in mind the seat diam. on the heads is usually limited or set by what can be machined ,the coil bind or stack height and installed height must match the cam lift clearance and and both the open and stationary s, issues like inside dia. and distances between retainer and valve guides ETC. dictate the valve seals that can be used, spring loads must match the application, yes
when you select a cam, the cam supplier will generally suggest matched springs, and an installed height and matched components, and yes they have a marked interest in your engine performing well , so they will tend to give good info, they are NOT just trying in most cases ,to increase their profits by selling you stuff you don,t need.
yes stock springs are fine IN SOME APPLICATIONS, but you must ALWAYS check spring clearances and loads and valve train geometry
theres a big difference in spring quality between the O.E.M and the better aftermarket springs and running double or triple springs can at times be an option, remember lighter valve train components usually reduce stress, allow less spring pressure and resulting valve train wear, and tend to increase the rpm range.
btw your generally fighting a hopeless battle if your expecting complete valve control with any hydraulic cam design much over about 6400rpm-6500rpm
and your valve spring load rates do effect the roller lifters life expectancy, high load rates decrease the cams life span and increase wear issues

Smokey Yunick discovered that valve springs raise the operating temperature of engine oil more than combustion heat with his own version of today's "Spintron" spin fixture. From the Circle Track Archives

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keep in mind that you can use EITHER self aligning rockers OR guide plates BUT NOT BOTH at the SAME TIME with properly installed screw in rocker studs
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http://www.racingsprings.com/

http://www.iskycams.com/psisprings.php

http://www.psisprings.com/index.php?opt ... view&id=17

http://www.ovaltracking.com/tech/2006/i ... ive-3.html
self aligning rockers have ridges to prevent the rocker from moving off the valve stem

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left is a BEEHIVE SPRING,with small light weight retainer, RIGHT SIDE STANDARD SPRING standard retainer
http://www.dougherbert.com/1445beehives ... 22853.html

http://www.jegs.com/webapp/wcs/stores/s ... 7_-1_10699

http://www.carcraft.com/techarticles/vo ... g_upgrade/

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Id use any decent quality springs from any NAME BRAND manufacturer regardless of brand if the clearance and load rate specs matched the required clearances and loads, naturally the manufacturer of the cam has a vested interest in your engine running correctly so their advice should be taken seriously, but because its a very competitive market they will rarely point out the BEST springs, opting for the slightly more that adequate choice to keep the costs lower and make the sale, knowing that in most cases that's going to be the best compromise , but I certainly would avoid "deals" from sources like EBAY where your not sure what your getting and they have little to loose selling cheap imported junk, after all its YOUR engine that's going to be damaged if they fail, and quality COSTS more than JUNK!

as a general guide flat tappet cams , and mild hydraulic roller cams will want about a 120 lb seat and 330-340 lb over the nose full open spring load rates

its not until you get into the solid roller cams that the load rates jump significantly

naturally you'll want to read the cam manufactures info on clearances, posted on the cam cards and their web sights , as to suggested installed height, spring diam. and load rates before selecting springs or setting up your clearances and the installed heights and spring bind heights do vary a good deal, and don,t forget to verify the valve train clearances and geometry, as a general rule, sbc hydraulic cams used with stock heads,will work with lifts of 0.475 and under, and work with most stock springs
yes we all know guys who (SUCCESSFULLY??) installed a .500 lift cam with good result (SO FAR), but without checking clearances carefully that also a great way to have problems, and its that not checking that results in most of the problems I constantly see, as a result of cam swaps, youll also want to keep in mind that the DURATION and LSA (LOBE SEPARATION ANGLE) play a part in the clearance issues, between the valves and pistons


obviously getting the clearances wrong, or over reveing the engine can cause problems

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http://www.centuryperformance.com/check ... g-144.html

http://www.racingheadservice.com/Inform ... arance.asp

http://www.cdxglobal.com/content/sample ... ear_WS.pdf

http://www.chevyhiperformance.com/techa ... index.html

http://www.carcraft.com/howto/116_0701_ ... index.html

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ISKY CAMS SELLS CUTTERS LIKE THIS TO NOTCH PISTONS
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viewtopic.php?f=52&t=1751&p=4387#p4387
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theres hundreds of ways to destroy an engine, but a common route is trying to compress solid objects in the combustion chamber,where theres not nearly enough clearance,or having the valve train bind up due to clearance issues or reveing the engine above its valve control limitations. lack of lubrication and too much heat can easily be factors but...
failure to keep the pistons from hitting the valves, bending valves, ,over reveing the valve train and having un-controlled valve movement, or having chunks of piston,that detonation can break loose, being compressed against the heads,can result in the cracked cylinders, and bent rods like the pictures below show
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any part can fail but running valve springs up near their minimum clearance and maximum rpm range limitations is just asking for problems
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IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
grumpyvette

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Re: sellecting valve springs

Postby grumpyvette » September 30th, 2008, 3:37 pm

BTW TESTING BY SMOKEY YUNICK, proved theres more HEAT transferred to the engine oil from the valve springs and rockers, and bearings than from combustion!......think about that! without oil flow valve springs, the friction from them flexing builds heat very rapidly and they eventually loose much of their strength,if not constantly bathed in a shower of oil to absorb and transfer the heat out of the valve train, so when some guy starts suggesting you limit the oil flow to the rockers and springs hes in effect planning on limiting the engines durability, you need full oil flow to the valve train assembly....now of course that oil needs to be returned to the sump, cooled and recycled thru the engine efficiently, but its mandatory that its flowing over the valve springs and rockers for engine durability, and if the contact area between the valve stems and guides, rockers, and the valve springs are not kept reasonably well lubed it frequently results in those (UN EXPLAINED )dropped valves, busted springs and the resulting carnage those can cause.....limit oil flow to the valve train and the spring tension can drop rapidly as the springs anneal , of fracture under hundreds of cycles and hundreds of pounds of spring and inertia loads and from excessive heat that can build up in only a minute or two of high rpms without oil flow bathing the valve train

keep in mind in most cases higher valve spring pressures don,t tend to make the engine significantly harder to spin because theres an equal number of valves closing at the same time there are valves opening ,thus much of the increased force or load is off set, but the stress on the lifters and cam lobes, and lifter contact points on the lobes IS increased, so a billet cam core is a nearly mandatory choice at above about 400 ft lbs of valve spring pressure for long term durability and with the faster acceleration rates on most roller cam lobe designs the higher pressures become mandatory to maintain high rpm valve train stability, if you loft a roller lifter valve train,at high rpms, under valve float conditions it frequently and rapidly leads to valve train failures, so verify the required valve springs and clearances with the cam and cylinder head manufacturers before installation

having a REV-KIT that retains the lifters in their bores, to maintain oil pressure, even if the rocker comes loose or push rods breaks is a good idea
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on many hydraulic roller lifter applications a REV KIT on hydraulic roller lifters adds several hundred RPM to the power band before valve control issues develop
BTW theres useful info in these threads also
youve installed 1.6:1 ratio rockers and the pushrods rub...in the guide slots in the cylinder heads,
this is a common problem,easily solved...
YOU NEED A louis tool, YOU WANT ABOUT .060 CLEARANCE, IT MAKES THE JOB EASY
This tool was designed to simplify the modification needed when using 1.6 rocker arms on SB-Chevy heads. It allows you to use a hand drill with a 5/16'' bit to elongate the pushrod slot exactly in line with the existing slot, thus eliminating the need for guide plates.
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stock stamped rockers are cheap but the ratio is usually not precise and the slots for the rocker studs can bind at high lift plus they easily restrict 10-15 hp in friction losses.
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roller tips are usually more precise ratio rockers but don,t look for any huge reduction in friction

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true roller rockers can frequently free up 15-20 hp in reduced friction.

WATCH VIDEO
http://www.youtube.com/watch?v=DxROQtv7 ... dded#at=31
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viewtopic.php?f=52&t=2746

viewtopic.php?f=52&t=2661

http://www.chevyhiperformance.com/tech/ ... to_11.html

viewtopic.php?f=52&t=1751

viewtopic.php?f=52&t=6491

viewtopic.php?f=52&t=1716&p=4250&hilit=beehive#p4250

viewtopic.php?f=52&t=1489

viewtopic.php?f=52&t=1751&p=4387#p4387

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viewtopic.php?f=52&t=2166&p=5840#p5840

read
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http://www.chevyhiperformance.com/techa ... index.html

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what the stock OEM roller lifter valve train looks like

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MouseFink wrote:The Cadillac CTS-V lifters, GM-88958689 (box of 16 - $296.36 msrp) will not withstand bone crusing valve spring spressure for long. The Cadillac CTS-V lifters are lighter weight and are no stronger than standard Chevrolet LS-7 lifters, [b][color=#0000FF]GM-12499225 (box of 16 - $139.76 msrp)[/color][/b] or GM-17122490 (box of 8), AC Delco HL-224 hydraulic roller lifters. If you use standard or aftermarket SS valves and valve train components with more than 130 - 150 lb. seat pressure and 330 -360 lb. open pressure, you are better off using hydraulic roller lifters that can withstand that much pressure, such as Comp Cams 875 Reduced Travel or Comp Cams 15850 Short Travel hydraulic roller lifters with restricted oiling.

The Chevrolet LS and Cadillac CTS-V lifters are designed to be used with less than 100 lb. seat pressure and 300 lb. open pressure. That is because instead of bone crushing valve spring pressure, the Chevrolet LS and Cadillac CTS-V engines use titanium locks and retainers with sodium filled and titanium valves. Those lifters also have restricted oiling for moderate load beehive valve springs. Those type valve springs have progressive pressure and do not need to be flooded with oil for cooling. The Chevrolet Z06 and Cadillac CTS-V engines are supercharged and don't need to be be spun up to the stratosphere to make over 500 HP.BTW...You don't have to specify "LS7 lifters" anymore. You can just call them "Chevrolet roller lifters" because GM uses the GM-12499225 (AC Delco HL-124) roller lifters as service replacements in all 1991-2013 V8 engines, except the Cadillac CTS-VR engines.

STOCK dog bone design hydraulic enclosed wheel roller lifters are generally designed for less than .550 lift and less than 6000rpm
the stock Chevy hydraulic roller lifters , dog bone and spider springs don,t always work reliably, ALL THE TIME with engines having over .500 lift or when spun over 6000rpm, its not all that rare for the lifter ,retainer to bend the retainer spring allowing the lifter to spin sideways, in the lifter bore, resulting in a destroyed cam, thats why Ive suggested BRAND NAME ,AFTERMARKET RETRO FIT CAM COMPONENTS BE USED
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roller blocks have taller lifter bores, because roller lifters are taller, and a provision to bolt the lifter retainer spring, but they can be very easily used for the earlier flat tappet lifters if desired by simply removing the spider(SPRING RETAINER), keep in mind most roller blocks use one piece rear seals
on Chevrolet engines, Crane recommends that a .030-inch-wide and .030-inch-deep groove be machined or filed into the bottom band on the distributor shaft as shown (arrow) to provide lubricant to the distributor gears. Place the groove on the distributor so that when timed properly, the groove will face the camshaft. With the distributor in this position, oil will spray both the distributor and the cam gear to significantly reduce gear wear. This trick can improve gear life for any type of camshaft. Ford engines have an oil passage plug that points directly at the distributor gear. A .025-inch hole can be drilled into the plug to lubricate these gears.

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http://www.lunatipower.com/Tech/Valvetr ... metry.aspx
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push rod to short
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push rod to long
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push rod length correct

viewtopic.php?f=44&t=2839&p=7344&hilit=adjustable+guide#p7344

viewtopic.php?f=52&t=126&hilit=louis+rocker
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and you may need too use the correct adjustable guide plates when you find the push-rod alignment is in need of minor tweaking to get the clearance and geometry correct
the heads and rockers used obviously effect the required clearance, but you'll usually want at least 60 thousands clearance on the push rods to slot measurements and you'll want to rotate the engine thru two complete revolutions while verifying that clearance, while watching the push-rod geometry as it changes as the rockers move thru their arcs
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using a louis tool, this tool is a GUIDE /tool for use with a high quality DRILL,its made of HARDENED STEEL that FORCES the DRILL BIT to drill thru the head to correctly lengthen the pushrod slot for increased clearance, they usually come WITH INSTRUCTIONS AND THE NECESSARY DRILL

you should also keep in mind that a roller cam valve train with the same lift and duration can provide a good deal more port flow and resulting power.
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but even roller cams can wipe out lobes if the valve train components or valve train lubrication,and geometry is not set up correctly
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most sbc factory heads will allow a lift of about .470 with the factory springs and clearances, a few will allow up to .530, but the only way you can be sure is to verify clearances

viewtopic.php?f=52&t=181

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using a valve spring micrometer and measuring spring bind helps verify clearance


the result of not verifying valve train clearances,full lubrication and valve spring load rates
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you really need to talk with the tech guys at CRANE, ISKY, CROWER,ERSON,ETC, about your goals and matching components to the application before making any changes, to the valve train or selecting the stock OEM components based on the lower cost, some OEM roller lifters and cams are INFERIOR quality and HEAVIER than the CRANE, ISKY, CROWER, ERSON, ETC aftermarket components, the OEM roller lifters that use the dog bone and spider retainer system tend to limit your rpms and choice of cam lift and duration more than the aftermarket components designed for higher rpms and lift, naturally the heads and valve springs and rockers, push-rods, and rocker stud girdles (IF USED) and the geometry must match the application, and as the spring loads increase the use of a BILLET CORE CAM is advised, no OEM component hydraulic roller lifter valve train is likely to work well much pastv 5800rpm-6000rpm, but the better aftermarket designs can add several hundered rpm to the power band with the correct valve springs and components being used and care must be taken to assure lots of cooling oil flow, the correct clearances and valve train geometry ,and not getting into valve float rpms or you'll quickly destroy a roller valve train


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these hydraulic roller lifters rarely work well past 5800rpm-6000rpm MOST GUYS WHO INSIST THEY DO, don,t realize that the lifters are not maintaining firm contact with the cam lobes,or the shock loads on the valve train cause problems,which they may not see until they have component failure problems and depending on wildly varying components and rpm levels and frequency of use those components may last for years or only days under such abuse

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this type will frequently add 200-300rpm to the valve trains max rpm stability

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swapping to SOLID ROLLER LIFTERS , can frequently add over a 1000 rpm more with the correct cam lobe and stiffer valve train springs and components


keep in mind that weak link in the chain idea, in many engines with upgraded valve springs the rocker studs benefit a great deal from a stud girdle as it significantly reduces rocker stud deflection, certainly by the time your looking at using more than 160 lbs of valve spring pressure use of a rocker stud girdle and quality roller rockers, and the correct geometry, clearances and checking for significant oil flow over the valve springs becomes almost mandatory to maintain durability


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yes I know your most likely skipping reading thru the sub links, in this and other threads, but thats a mistake that can easily cost you hundreds of dollars and weeks of work you could easily avoid, knowing what your looking at and how and why it functions as it does is critical to long term durability
viewtopic.php?f=52&t=196

viewtopic.php?f=52&t=1376

viewtopic.php?f=52&t=399

viewtopic.php?f=52&t=5902

viewtopic.php?f=52&t=5341

viewtopic.php?f=52&t=4957

viewtopic.php?f=52&t=2746

viewtopic.php?f=52&t=528

viewtopic.php?f=52&t=553
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs

Postby grumpyvette » October 24th, 2008, 8:52 am

HEY GRUMPYVETTE, I've found that I have a collapsed lifter ( I'm almost positive) and as long as I'm in the engine I'm going to get rid of the flat tappet and go with a hyd. roller. The current one is 218/224 duration @ .50 with .462/.469 lift with 1.5 rockers. The one I'm looking at is 222/230 duration @ .50 with .518/.539 lift with 1.5 rockers. I'm pretty sure it will work with my computer. My concerns are---the valve springs I have are good to .575" lift and have 105 lbs seat pressure. The guy @ Crane cams said to just add .030" shims under the springs to get to 150 lbs seat pressure. With these shims, won't I be too close to completely compressing the springs with the increased lift? Also, how do I figure out the length of the new push rods? (I'm not an engine guru :D ). Thanks in advance!
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this cam buttons correctly installed but thee retainer plate tabs have not been bent up to lock the bolt heads from rotating

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correct length..................too short............................too long


General Valve Spring Pressure Recommendations*
Camshaft Type Seat pressure (pounds) Open pressure (pounds)
Hydraulic and solid flat tappet 100-130+ 270-350+
Hydraulic roller .................... 105-135+ 280-350+
Solid roller (street pattern)..... 150-180+ 450-600+
Solid roller (race pattern)....... 190-300+ 600-1000+

the thinner the shim the closer to the heads surface, it should be installed, in any stack of shims under the valve spring, seat, and theres no reason you can,t simply remove the .003 shim to get the correct clearance if thats whats required to do so!
the hardened STEEL VALVE SPRING cup is designed to locate the spring and not wear easily if the spring oscillates on its seat at high rpms, the copper shims will quickly disintegrate if in direct contact with the oscillating valve spring base.
Obviously you never want to operate an engine up into valve float rpms where valve train damage is certain to eventually result and a constant spray of oil on the valve springs extends your valve trains life expectancy

viewtopic.php?f=52&t=6491&p=20681&hilit=spring+cooling+spray#p20681

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here is what results from soft valve spring shims in direct contact with oscillating valve spring base

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watch videos
http://www.youtube.com/watch?v=_REQ1PUM ... re=related

http://www.youtube.com/watch?v=019Jyn9o ... re=related
notice how the valve springs glow red hot if not constantly bathed in oil flow, notice how the valve springs rotate in the valve seats, most people find it hard to believe that more than 40% of engine heat is generated in the valve train

viewtopic.php?f=52&t=181&p=215#p215

http://www.supercarsunlimited.com/info/ ... prings.htm

http://www.hotrod.com/techarticles/engi ... ewall.html

the .030 shims reduce the valve lift clearance from .575 to .545 and add the necessary load to the valve train, NOTHING in the push rod geometry changes, no new push rods are needed, due to adding shims.

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roller lifters being taller require shorter push rods, I was not trying to answer that part of the question as that should be obvious...sorry I was not clearer
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keep in mind STAYING OUT OF VALVE FLOAT RPMS ,use of the correct installed height valve spring height, spring load rates and hardened shims and are required between the valve spring base and the spring locator seat/cup under the valve springs that locate and protect the cylinder heads or at higher rpms the valve springs harmonics , make the valve spring base vibrate ,and eventually eat thru the soft shims
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in an ideal world the rocker pushes strait down the valve stem center line to reduce friction,but having the rocker wear pattern centered on the valve tip is far LESS important than having it rather narrow indicating less side thrust or drag on the valve
and having the rocker geometry a bit off as long as the clearances are correct, is unlikely to cause noise issues as much as long term valve guide wear issues.
Noise is usually the result of clearance issues like the slot in the rocker or rocker ball or body binding on the rocker stud or rocker adjustment nut, or the valve retainer touching the rocker body or spring bind etc. or badly adjusted valves , and Id bet 80% of the engines I see have improperly adjusted valves of valve train clearance issues

for those that don,t know, these are BEEHIVE springs that allow a lighter and smaller titanium retainer and the basic design makes the springs far less subject to harmonics at mid too upper mid rpm ranges at lower load levels

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left is a BEEHIVE SPRING,with small light weight retainer, RIGHT SIDE STANDARD SPRING standard retainer
http://www.racingsprings.com/
(beehive)

Would .006" be enough room to spare in spring compression"

that depends on both how accurate the valve train measurements are and how they calculate the clearance,......normally when the valves springs max lift height is listed or posted rated at a .575 lift,etc. theres a .050-.060 thousands extra clearance between the true spring stack height and the advertised max valve lift IE your advertised .575" max lift spring is designed or has a total of .575"+.050"=.625" between max open height and max valve spring height
.006 clearance would not normally be used or suggested as safe, youll need to know the true coil stack and true installed heights as installed

example look here

http://www.racingsprings.com/PDF/beehive.pdf

look at the first spring listed

max lift is listed as .600 lift
installed height 1.800
max lift @ 1.200 to get that .600 lift
BUT COIL STACK IS AT 1.140, thats .060 more, giving the necessary clearance

just be aware that the retainer to valve seal or retainer to valve guide or rocker slot to rocker stud or a few other clearance issues might limit what you can actually use as lift with the valve train, and that valve keepers come with different locking groove heights allowing the valve spring retainer to have the valve spring installed heights

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Most valve springs are reasonably cheap, so I usually strongly recommend getting the correct clearance work done to the heads and using springs at least very similar to those the cam manufacturer recommends for the application in both clearance and load rates, theres not much sense in potentially ruining an engine with valve control issues if it can be avoided.
yes standard springs generally will FUNCTION with a mild roller cam, but the lifter weight and ramp speeds won,t be ideally matched so your better off using the manufacturers suggested springs or at least very similar to those the cam manufacturer recommends for the application in both clearance and load rates.

viewtopic.php?f=52&t=181

http://www.racingsprings.com/
(beehive)

http://www.ovaltracking.com/tech/2006/i ... ive-3.html
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VERIFY YOUR ROCKER TO RETAINER CLEARANCES


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after youve selected the new cam and new springs and thats fine but in most cases new springs require the clearances be verified and that usually requires new valve spring shims,retainers,keepers or machine work on the heads to get the correct installed valve spring height, spring load rate and clearances, failure to do so usually results in valve train problems.
many valve train parts failures are the result of clearance or geometry issues, or insufficient lubrication, factors that must be checked, before use.
ID suggest you always closely examined each of the roller lifters before re-use, looking for signs of wear but in about 75% of the cases hydraulic roller lifters with under about 15,000-20,000 miles of use should be fine for re-use
in many cases, of early valve train failure its simply a lack of taking the time to verify clearances and geometry or even the knowledge of how to do it correctly,or lack of the tools required that gets cam swaps into trouble, parts fail, and theres sometimes no easy to find reason, but if you don,t get the clearances and geometry right before use, your stacking the odds heavily against long term durability


youll also want to verify piston to valve clearances and correct quench

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keep in mind that the intake valve usually starts to open well before the piston reaches TDC on its exhaust stroke, and continues to extend out towards the piston after it passes TDC and follows it down into the bore as it descends on the intake stroke, generally closest contact points are in the 20 degrees btdc too 20 degrees atdc, obviously exact potential clearances are dependent on both cam timing and cam indexing

ID ALSO POINT OUT THAT A ROCKER STUD GIRDLE ADDS A GOOD DEAL MORE STABILITY TO THE VALVE TRAIN
viewtopic.php?f=70&t=4836&p=13219&hilit=indexing+plugs#p13219
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http://www.cpgnation.com/forum/comp-cams-how-valve-spring-tech-2047.html

http://www.lunatipower.com/Tech/Valvetrain/ValveSpringTech.aspx

http://www.enginebuildermag.com/Article/47631/the_truth_about_valve_springs.aspx

http://www.chevyhiperformance.com/tech/engines_drivetrain/cams_heads_valvetrain/0612ch_head_build/index.html

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IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs

Postby grumpyvette » November 22nd, 2008, 12:23 pm

if you don,t think use of the correct valve springs and rockers matters heres the dyno results on a 496 BBC chevy engine with a new set of valve springs and roller rockers, obviously if correctly selected,they can make a difference
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THINKING OF ADDING A REV KIT?
first Id point out that adding a rev kit is expensive and won.t do a darn thing for your application but INCREASE the loads on the roller lifters thus INCREASE the likely hood of failure since your limited to under 6000rpm, where a correctly designed valve train with aftermarket beehive springs, light weight titanium retainers and a stud girdle mounted to stabilize roller rockers is likely to perform just fine, especially if your trying to maximize dependability
Ive seen after market rev kits come apart, under high revs but they were NOT AIR FLOW RESEARCH brand, rev kits are designed to hold the lifters on the lobe ramps at high inertial loads, under 6000rpm the correct valve train should easily do that without a rev kit.

http://airflowresearch.com/hydra_rev.php

http://www.flatlanderracing.com/revkitsafr.html

stock springs and a stock valve train may get marginal above 6000rpm but a correctly designed hydraulic roller valve train can easily handle 6000rpm
if your worried get shaft mounted rocker arms and the beehive springs and titanium retainers

http://www.racingsprings.com/
(beehive)

http://www.compperformancegroupstores.c ... y_Code=BEE

the ideal answer is not to overload the rollers on the cam with heavier loads but to lower the weight/enertia the valve train is subjected too, and control harmonics, and lighten the valve trains tendency to want to allow the lifter to lose contact with the cam lobe ramp, adding a rev kit increases the loads on the cam and roller lifter, under 6000rpm thats not necessarily a good idea when theres other options

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for those that don,t know, these are BEEHIVE springs that allow a lighter and smaller titanium retainer and the basic design makes the springs far less subject to harmonics at mid too upper mid rpm ranges at lower load levels

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http://www.racingsprings.com/
(beehive)

http://www.popularhotrodding.com/tech/0607phr_camshaft_basics/photo_32.html

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http://www.chevyhiperformance.com/techa ... index.html

http://www.chevyhiperformance.com/techa ... index.html

http://www.superchevy.com/technical/eng ... index.html

http://www.youtube.com/watch?v=Zr_n0cL46NM

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manley wrote:Coil Bind And Valve Float

Another area where large gains in valve spring longevity can be realized is in paying close attention to coil bind. Coil bind is a condition in which the maximum lift of the valve exceeds the maximum allowable compressed height of the valve spring before the spring coils contact each other and create a bind. Running a valve spring in a condition where it has reached coil bind is going to instantly create very destructive forces within the valve train.

However, running a valve spring in a condition where it has excessive clearance between the spring coils at maximum valve lift can also contribute to surprisingly destructive forces being generated within the valve train, especially in the valve spring itself.

Classic engine building 101 typically teaches that a valve spring should maintain a bare minimum of .060-inch clearance between the spring coils at maximum valve lift, and that more clearance is usually better because additional clearance is typically thought to provide additional safety margin. However, excess clearance (typically over .100-inch) between the spring coils will allow a phenomenon known as “spring surge” to take place as the valve is being opened and closed.

In the occurrence of spring surge the middle portion of the spring coils can oscillate or “bounce” uncontrollably between the upper and lower portions of the valve spring as the valve is opening and closing. This surging motion reduces the stability of the valve spring. Reduction in spring stability can induce premature valve float.

Valve float is an extremely destructive condition where the valve spring loses the ability to control the valve motion and, consequently, the valve can slam repeatedly into the valve seat instead of closing in one smooth motion. During valve float the valve can also possibly collide with the piston during the opening and closing events, especially at elevated RPM levels. As Manley’s Bob Schmalz says, “Valves can take all the open pressure you can give them. They see the most stress in valve float.
Even if valve float is avoided, the phenomenon of valve spring surge will almost always result in a bare minimum of prematurely broken valve springs. As such, Manley typically recommends that valve springs should be installed and run at .070-inch from coil bind when the valve is at maximum lift. In testing and experimenting with a wide range of installed heights, Manley has witnessed a Stock Eliminator engine increase its effective ceiling by 300 RPM when running the valve springs at close to coil bind.
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs

Postby grumpyvette » November 22nd, 2008, 12:24 pm

just a few points

http://www.cranecams.com/bulletins_listview.php?s_id=7

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most manufacturers IDENTIFY OR mark cams under the timing gear mount surface
actually verify clearances and rocker geometry
at
seated valve
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mid lift

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full lift
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long slot rockers are far less likely to bind on rocker studs

witness rub mark should be narrow, having it close to the valve center line is not as critical as having it narrow but try to have it close to center
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lets be clear, before going further, if your rockers bind on the rocker studs or push rod guide plates, and you have verified proper rocker geometry, with the correct push rod ;length, your describing the rocker binding at location (B) not location (A) or (C) , location (A) is frequently the result of using the wrong adjustment nuts with your rockers, this tends to bind the upper rocker slot to the sides of the adjustment nuts,frequently when you swap to a different style to use a rocker stud girdle.
location (C) can be avoided with BEEHIVE type valve springs and retainers OR machining rockers for additional retainer to rocker clearance.

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if thats the case the push rods or the rocker studs or the guide plates are wrong for the application OR you never had the cast rocker bosses in the heads correctly machined for the screw in studs

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standard screw in rocker studs to use with or without guide plates require the rocker stud boss be machined for required clearance
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EACH type of engine and every set of rocker guide plates and studs will effect how far the rocker boss must be machined for clearance but on most sbc engines the boss is machined down about .360, CHECK WITH YOUR MACHINIST AND HAVE THE PARTS AVAILABLE TO MEASURE
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there ARE screw in rocker studs that can be used WITHOUT machining the bossed but they CAN NOT be used with guide plates and DO frequently result in cracked rocker bosses.

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stock cast rocker bosses must be machines to gain clearance for guide plates and screw in studs


setting up the installed height and clearances and selecting the correct load rates is both a well understood and reasonably easy to do procedure, requiring the valve seats ,correct shims, springs retainers, locks and machine work.
if you know the required installed heights and clearances and spring load rates its just not that difficult for a decent shop to order and assemble the correct parts, or do the required guide or seat mods

http://www.compcams.com/Technical/FAQ/ValveSprings.asp
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hydraulic roller lifters tend to stay in the lifter bores when a push-rod breaks they tend to move up just far enough to allow the lobe too pass under the roller , the link bar tends to prevent them from being thrown loose in the lifter gallery

these come in different designs but youll want ones matching your application
http://www.summitracing.com/parts/PRO-66789/
http://www.summitracing.com/search/Part ... -Checkers/

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viewtopic.php?f=52&t=2091

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http://www.summitracing.com/parts/CCA-7901-1/

load rates over about 135lbs seat and 450lbs on the ramp nose tend to be both un-necessary and put a significant extra wear on the valve train

heres the hydraulic roller cam IM running on the street, it pulls to 6300rpm just fine with out a rev kit

http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=119661&lvl=2&prt=5


heres the springs THEY SUGGEST YOU USE

http://www.cranecams.com/?show=browseParts&lvl=3&prt=123&action=partSpec&partNumber=99838-16

NOTICE the seat and full lift load rates

heres some info

http://www.cranecams.com/?show=valveSpringOpen

btw Im running different springs that spec at 145 lbs seat and UNDER 390 lbs at full lift with 1.6:1 ratio rockers at .595 actual lift, and pull 6300 rpm just fine

http://www.racingsprings.com/PDF/beehive.pdf
similar too the #1520, but Im running TRICKFLOW ALUMINUM HEADS factory set up for 1.45 diam. springs that were custom machined and clearanced


heres a different cam I tried

Crower_HR_00471_555_560.JPG


notice the suggested spring pressures are even lower but again under 400 lbs at max lift and that cam made more upper rpm hp but lacked the low rpm tq I wanted on the street application

always call the cylinder head manufacturer for their input on rocker stud girdles,BEFORE PURCHASING THEM< because rocker stud spacing, and stud angles can vary, between head designs and models

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http://www.summitracing.com/parts/crn-11759-16
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cranes gold roller rockers are decent quality rockers for a small or big block chevy,Ive used those, ERSON, CROWER and COMP CAMS ROLLER ROCKERS, many of them come with jam nuts that require a 3/16" allen key
and look a great deal like these posted here below

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but these are NOT locking jam nuts designed to work with a rocker stud girdle
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http://www.summitracing.com/parts/tfs-3 ... /overview/
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rocker stud girdles require significantly longer shank jam nuts , but you need to mount the rocker stud girdle up out of the way so the upper surface of the rockers can,t touch the lower surface of the stud girdle at full lift

notice the recessed hex on the rocker stud lock nut used with the girdle, cranes roller rockers require a adjustment nut with a .600 diameter , to keep the rocker with its slightly larger slut from deflecting to the side, as the body of the jam nut helps stabilize the rocker , and the nuts are made with matched thread pitch and a stud girdle with the correct stud spacing.
stud girdles significantly strengthen the rocker studs because all 8 studs on a cylinder head resist movement of each individual stud as its subjected to stress as the cam lobe compresses the valve spring and the stud tries to deflect, not just a single stud.... shop carefully and ask lots of questions and its usually a good idea to buy matching components from a single manufacturer if possible for all the valve train components as it tends to avoid mis-matched parts causing clearance or geometry issues.

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many guys would like to retain short valve covers or use original valve covers, but use roller rockers
obviously the clearance issue depends on both the valve covers and rockers used in the application, but in most cases you can your full roller rockers if you DON,t use the tall jam nut locking adjustment nut designs, as its the jam nuts not the rockers causing the clearance issue
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standard long jam nuts are the cause of the clearance issue most of the time
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shorter lock nuts provide required clearance
http://www.summitracing.com/parts/CCA-1321N-1/


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THERE ARE VALVE COVER SPACERS AVAILABLE ALSO


the forged steel rockers generally clear in most application if the short nuts are used

viewtopic.php?f=52&t=126&p=1193&hilit=ratio+rockers+louis#p1193

viewtopic.php?f=52&t=399

viewtopic.php?f=52&t=528

viewtopic.php?f=52&t=7716

viewtopic.php?f=52&t=5902

viewtopic.php?f=52&t=10696&p=46481#p46481

viewtopic.php?f=52&t=4957

viewtopic.php?f=52&t=2661

viewtopic.php?f=52&t=2746

viewtopic.php?f=52&t=181
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IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs

Postby grumpyvette » November 24th, 2008, 1:49 pm

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this charts based on a 350-383 Chevy or similar size engine, but its a good rough guide on most engines under 400cid displacement on matching the duration to the intended operational rpm band , remember, you’ll still need to verify ALL clearances, valve train geometry and spring load rates with any new cam install.
on engines over about 430-440 cubic inches of displacement youll need to add some duration & lift for increased flow rates to get the same basic power band
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs

Postby grumpyvette » November 27th, 2008, 9:13 am

The BEEHIVE springs and TITANIUM retainers ,(On a street car engine), can easily add both several hundred RPM and several hundred dollars to the engine cost/potential.
In some cases thats worth the extra cost,but in most cases I doubt youll spend enough time pushing the upper rpm limits on the engine to justify the cost, over well matched conventional dual valve springs.
And for the same basic reason guys tend to build 383 SBC and 496 BBC combos rather than 302 SBC and 427 BBC engines, the much better low and mid rpm torque curves are far more useful on the street strip combos most guys build than the few hundred extra RPMS that you might get, now
obviously having BOTH, the INCREASED displacement and the lighter spring load rates that still maintain valve control is a PLUS, and theres little doubt theres advantages in running beehive springs in some cases
but its been my experience that both a 383 sbc and 496BBC designed to run pump octane gas, can spin up into the mid 6K rpm range, with well matched conventional dual valve springs before the the BEEHIVE springs and TITANIUM retainers become and advantage and on the street thats usually not done frequently.
keep in mind that with well matched conventional dual valve springs,and spring dampers most manufacturers supply in their cam installation kits if you buy the suggested matched components, the harmonics tend to cancel out some of the problems seen with single springs
Image

http://www.summitracing.com/parts/sum-900013/overview/

http://www.summitracing.com/parts/sum-900012/overview/

Image
Image
Image
Image
Image
Image
Image
Image
youll eventually want a few tools like a valve spring tester and spring height mics
Image
Image

Standard valve trains, maybe with a rocker stud girdle , and roller rockers can easily maintain valve control up to the mid 6K rpm band, and with cams designed for street /strip use the duration and lift must be moderate for long term durability, and street-ability in low rpm driving characteristics, and a need to run pump gas, compatible compression ratios, unlike a race combo, that extra few rpms is not a huge plus in most cases.
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
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Re: sellecting valve springs

Postby grumpyvette » November 30th, 2008, 12:00 pm

Ive tried all the methods listed above.....but I keep coming back the the first method Ive used for 40 years...

I may be old school,but IVE never had a problem adjusting solid lifters,and will continue to do so with this method, keep in mind, I set my lash with a feeler tappet gauge at engine idle speeds, by backing the rocker nut off a bit on the rocker stud untill the rocker clicks and I can slide the tappet gauge between the rocker and valve tip, then tighten it at idle just to the point the clicking stops then I remove the tappet gauge
esentuallt the methods similar to the way I set hyrolic lifters, but on hydrolics you don,t use a feeler/tappet gauge and once the rocker nuts tightened to the point the rocker stops clicking you add an aditional 1/4 turn for preload

http://www.cadvision.com/blanchas/54pon ... ppets.html


Image

http://store.summitracing.com/partdetai ... toview=sku

http://www.sjdiscounttools.com/lis68050.html
Image
http://store.summitracing.com/partdetai ... toview=sku
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs

Postby grumpyvette » December 5th, 2008, 4:37 pm

HEY GRUMPY?
I have some comp beehives on my bbc, part #26120
I also have a lunati voodoo hydro roller part # 60212
I have 1.72 ratio full roller rockers up top, I've cycled the engine through many times and checked clearance and have just a smidgen above .060 clearance in the middle.
This isnt a dedicated track car, just for street, and I dont plan on ever going above 5500rpm with it and have a rev limiter just to make sure, but does that amount of clearance with those parts seem safe enough to you? I don't think comp makes a stronger beehive for hydro rollers, and I dont feel like respending money, I've read many things and some people say you should have .100 clearance in the spring, and others say .060 is fine, what has been your experience?

I've called comp and they said they should be fine. However, I highly doubt they are going to reimburse me 8k in parts over their springs. I do want to protect my 8k I put in there, but at the same time dont feel like shelling out $250+ for new valve springs when the ones I have are brand new.

And I checked these clearances with no oil in the lifters whatsoever, they were completely bled down.

The people that assembled them for me http://www.m2race.com said on the install sheet that the installed height is 1.890, the installed pressure is 160lbs, and that coil bind is a .625 gross lift.

Comp says these are good to .600 lift and with the 1.72 ratio I come out to .607 lift. The tech on the phone told me it should be fine.
Would you run em?



ASSUMING your figures and info are correct,if your installed height is 1.890 and coil bind is at .625 thats 1.265 height for stacked spring coils, add .050 for minimal clearance and youll see a .575 MAX valve lift on the cam, BUT..

http://store.summitracing.com/partdetai ... toview=sku

http://store.summitracing.com/partdetai ... toview=sku

comp shows a 1.23 coil bind height, so given your lift is .607 the installed height and other clerances are critical to finding out if it will clear safely, 1.890-.607=.660-.050 for clearance =.610 so youll be ok IF the true installed height is really 1.890,
now heres what ID do,IF you want extra clearance just to be safe, ID install valve keepers/valve locks that gave me an extra .050 lift
http://www.cranecams.com/?show=browsePa ... er=99099-1
by seating the retainer .050 higher on the valve stem....since youve got no intention of running on the ragged edge of the rpm band, changing the installed height will lower the valve spring loads slightly but in your application thats almost a total non-issue, and yes it may require longer pushrods to get the rocker geometry correct so think thru your changes carefully.

this older post should help

HEY GRUMPY?
How much lift can these springs handle? I've read two different things from different sources....One says they can handle .490 another says they can handle .550....What's the real deal? See links below...I appreciate any help rendered.
http://www.motorpartscentral.com/Produc ... delId=7726

http://www.trifive.com/forums/showthrea ... ght=RV943X




GOOD QUESTION, SO LET ME EXPLAIN REALITY, vs ENGINE BUILDING THEORY ,you might want to keep in mind theres differances in the way max lift is being measured in some cases.
ADVERTIZED & THEORITICAL VS REALITY AS INSTALLED
example
heres a chart and springs IVE USED

http://www.racingsprings.com/PDF/beehive.pdf


lets look at the last spring on the chart, #PAC 1520

its installed height is 1.880

coil bind is at 1.210
subtract 1.210 from 1,880 and you get .670, yet,its max lift is listed at .650, ok,
but any engine builder will tell you you really need a minimum of .050 clearance, before reaching coil bind, so the real max lift at this point is not .650 but .620 lift, AHHHH!
but thats ONLY if the valve train allows you that .620 clearance, if the valve guides,piston to valve,retainer to valve guide, or valve seals,the differance on hydralic lifters,between the lifter seats supported by oil pressure or measured without oil holding them up, rocker slot clearance or a dozen or more other factors are taken into account and clearances meassured, youll be lucky in the real world to see that .620 lift clearance, you might have only .590 quite easily, and require either more machine work, or differant retainers, valve keepers etc. to get even that .620 let alone the .650 listed, and yes you can get that .650 but it might require a few tweaks, machine work, and a differant installed height, etc.
I think what they are saying is , that if you just pull the old springs and install the new ones .490 is usually what youll see, do some machine work and check clearances carefully and in theory you get the larger figure.

If you need to change the retainer to valve height location ,youll WANT to first look at the valve locks and what fits your retainers & valve design

, look thru all the listings they have

standard and .050 offset

11/32, 3/8"

single,and multi grouve,

7 degree and 10 degree locks

Tech Line - 386-258-6174


http://www.cranecams.com/index.php?show ... 2&prt=2126

theres also differant valve spring retainer designs
http://www.cranecams.com/index.php?show ... l=2&prt=33

LASH CAPS

Image
They are used BOTH too add a bit of length above the end of the valve stem so the rocker body doesn,t contact the edge of the retainer, or to get the correct valve train geometry AND to provide a wider area for the tip of the rocker to roll on and protecting the valve stem tip.
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » December 27th, 2008, 4:19 pm

I posted this in the chit chat section and got a question


I got what I requested from SANTA ,two, new valve spring mics, my old ones were fairly worn and hard to read
Image

whats a valve spring mic and hows it used?"

http://www.jegs.com/i/JEGS/555/80535/10002/-1?CT=999

http://www.scpraceparts.com/valve-sprin ... 2-200.html

Image

your questions very common, its used to measure the distance or INSTALLED HEIGHT between the spring shims upper surface and the retainers lower surface that the valve spring occupys normally, the springs removed and the mics installed in its place, the retainer and valve keepers are put in place and the valve mics extended to raise the retainer and seat the valve in the head, thus you get the correct space or distance between the or INSTALLED HEIGHT between the spring shims upper surface and the retainers lower surface that the valve spring occupys normally,
most valve springs have a spec card that indicated their intended load rates and installed height an coil bind heights, and load rates are checked with this tool, and a dial indicator.Its rather common for shops to install new valve springs without doing the matching clearance checks on installed height required to prevent spring bind with a high lift cam, if the engine spins without binding they figure its fine! which may NOT be the case
shims placed under the valve spring allow you to shorten the installed height, btw the thicker shims are placed on the upper end of the stack.
you need to verify clearances and load rates to get the proper loads and not get into clearance issues,
keep in mind coil bind is not the only clearance issue, retainer to valve seal, and retainer to rocker among other clearances along with coil bind and installed height must be verified, lets look at a spring,
http://www.pacracing.com/Street_Strip_S ... of_16.html

Premium Nitrided Beehive LS1 Spring
OD: 1.290"
130 lbs @ 1.800"
337 lbs @ 1.150"
Lift: 0.650"

notice coil bind is at 1.080 "
so youll install shims to get the height correct at 1.800
Image

http://store.summitracing.com/partdetai ... toview=sku
Image

viewtopic.php?f=52&t=181&p=1690#p1690

testing valve springs is a WHOLE LOT EASIER with the correct tools like those linked in this thread



http://www.summitracing.com/parts/PRO-6 ... toview=sku

Image

http://www.summitracing.com/parts/CCA-5333/?image=large

read thru these also

viewtopic.php?f=52&t=1005

http://www.cylinderheadsupply.com/valve ... nAodymUULA

http://www.youtube.com/watch?v=PR8cDaum7ss

http://www.cylinderheadsupply.com/valve ... izing.html

http://www.articleclick.com/Article/Usi ... ool/952814

http://www.streetperformance.com/m/cats ... -tool.html

http://www.phatperformanceparts.com/Pro ... lick=37735

https://www.goodson.com/technical_suppo ... Guides.pdf

http://www.summitracing.com/search/Part ... ing-Tools/
Image

Image

Comp Cams Valve Guide Cutting Tool
Upgrading your camshafts to get more horsepower is a good idea. But here's the catch- if you're going to upgrade your camshafts, you have to do so as well for the rest of your valve train, especially the valve guides. The thing is, you're going to need bigger springs to be able to handle your aggressive camshafts. You'll need to modify your valve guides. What you need is the Comp Cams Valve Guide Cutting Tool. What you really want is to shorten your valve guides. This is to accommodate the high valve lift brought by your new camshafts. The shorter the valve guide, the more valve lift and the less stressed your valve springs will be. Professional, or even seasoned street drivers, know all too well the problems associated with improper valve train setup. The more strain you put on your springs, the more likely that they'll bottom out, or worse, even break under high engine speeds. You'll also likely experience 'valve float' wherein your valve springs can't pull back your valves at high rpm's (revolutions per minute), so you lose power. So make sure you set things up correctly with the Comp Cams Valve Guide Cutting Tool. This ultra tough tool works with three different-sized arbors. No matter how many valve guides you go through, this tool will cut them clean as a whistle. No more second guessing with your valve train setup. Do things right the first time around with the Comp Cams Valve Guide Cutting Tool.

http://www.rpmmachine.com/pioneer-valve ... ools.shtml

http://www.jegs.com/i/Comp+Cams/249/4720/10002/-1#

http://www.vtwinmfg.com/catalogs/cyr/pdf/1249.pdf

viewtopic.php?f=52&t=1159&p=2362#p2362

Image
Image


http://www.youtube.com/watch?v=lrO7J9gA ... re=related

watch the video above



geometry is obviously not this guys strong area

problem, rocker body can not be lowered to get the correct geometry, push-rod needs to be slightly shorter,than the current 7.2" to provide the correct clearance and geometry, but that can,t be done because of clearance issues.....look guys this is hardly rocket science,
if you cant move the rocker down you need to move one or both ends of the rocker UP, while maintaining the correct valve train geometry and clearances,the rocker needs to move up but the push rod needs to stay the same, so the problem is the valve spring and valve tip the rocker rests on is not tall enough to move the whole rocker assembly and geometry issue higher on the rocker stud, he may need to move both the push-rod length and valve tip higher to gain the required clearance, that could be as simple as adding valve tip lash caps,to add length to the valve tip or it may require longer valves, and different valve springs, or swapping to a different rocker design.
but in any case the current set of components are not going to work, so its obvious he needs to do a few clearance and geometry checks

Image

Image

Proper push rod length is absolutely critical for peak performance—minimizing bent or broken valve stems, guide wear, and energy-wasting valve side-loading friction.
With the lifter located on the round base circle, position the Push Rod length Checker (make sure you have the Checker with the proper diameter hole) over the stud. Ideally the Checker should contact the top of the push rod and the valve tip evenly at the same moment, should the Checker contact the push rod first, measure the gap between the front of the checker and the valve tip, and purchase a shorter push rod of the correct length. Should the Checker contact the valve tip first, measure the gap between the back of the Checker and the top of the push rod, and purchase a longer push rod.
the process of finding the correct length push rods not that difficult, you install the correct push rod checker for your application,on a rocker stud, install the adjustable push rod, in place of the stock push rod after roughly adjusting the adjustable push rod to the stock length once the cam is rotated so the lifter, your using to verify the correct length is resting on the cams base circle, and then you extend or shorten the adjustable push rod so the plastic push rod checker just rests on both the tip of the valve stem and the push rod checker as in the picture above, this gets you very close to the correct length, you then use the machinists blue or a magic marker and the rockers you will be using to determine the exact correct length by centering if possible but finding the minimum sweep mark width so the wear mark on the valve tip as close to the valve stem center line as you can get it and the minimum side loading on the valve stem is found. centering the mark is less important than minimizing the rocker tip wipe mark width
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » January 30th, 2009, 11:09 am

when setting up the valve train clearances ,one of the first steps is making 100% sure the rockers push strait down on the valve stems, failure to do that significantly increases drag and friction in the valve train, youll either run push rod guide plates or self aligning rockers, but NOT BOTH, to keep the push rods lined up with the valves ,you'll need to get the valve train geometry correctly adjusted, or you'll have problems, with rapid wear on the rockers or pushrods or valve stems and valve guides.
the reason you don,t run both is that your almost sure to have alignment or clearance issues if both are used, and not 100% correctly lined up, if only one is used theres a small bit of slack tolerated in the valve train alignment and geometry.
take the effort to check and recheck all the clearances and angles because doing it correctly both reduces friction losses and tends to allow the valve train to last far longer and rev higher

http://www.cranecams.com/pdf-tech-tips/mech-lift.pdf

adjustable pushrod guide plates

BBC

http://www.dartheads.com/products/acces ... lates.html

http://www.jegs.com/i/Dart/301/27001230-4/10002/-1

SBC

http://store.summitracing.com/partdetai ... toview=sku

bronze guides hold a film of oil better, wear less and can be sized tighter for a more precise, fit, so the valve will seat more precisely as it closes, it also tends to transfer heat from the valve stem to the heads more efficiently that a looser knurled steel inner valve guide surface

http://www.ferrea.com/catalog/2009/Dom_ ... Guides.pdf

http://www.aa1car.com/library/ar696.htm

http://www.minimania.com/web/SCatagory/ ... ticleV.cfm

http://www.hastingsinc.com/ServiceTips/ ... ciency.htm

http://www.enginebuildermag.com/Article ... oning.aspx

https://www.goodson.com/technical_suppo ... Guides.pdf

keep in mind shims under the valve springs can be used to raise the spring or shorten the valves installed height, valve locks and retainers can be purchased with non-O.E.M dimensions to adjust the valves installed height or spring load rates
you use either or both depending on the application
a .050 PLUS valve lock moves the retainer .050 higher on the valve stem with no other changes, a plus .050 retainer would move the retainer .050 higher with stock valve locks or an additional .050 if matched to .050 plus locks
if you used a plus .o50 retainer with a set of minus .o50 valve locks the retainer would remain at the stock height on the valve stem

there are fully adjustable timing gear sets available
http://www.usaperform.com/timing-chain- ... =4d&page=1

Image

why is it that so many of you gentlemen are so reluctant to actually take the time to measure valve train clearance, spring load rates and valve train geometry and make every effort to avoid doing things correctly?
yes it takes some knowledge, some tools and some time, but in the long run its gives you some piece of mind knowing its been done correctly, and your far less likely to have catastrophic engine failures as a result.

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=181

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=2746

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=2661
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » February 1st, 2009, 1:08 pm

this question comes up frequently
"If I were to order a set of heads from summit or who ever and I bought the bare heads rather than a set that were assembled would I have to send them to the machine shop for work or could I buy the valves, springs studs etc and do it myself? "

THE ANSWER DEPENDS ON WHICH HEADS YOU BUY FROM WHICH MANUFACTURER!

Ive seen several sets of bare heads that required HUNDERED$ of dollars in machine work, like doing a 3-5 angle valve job, clearance the push rod holes,decking the surfaces,combustion chamber mods, spring pockets needed machining , stud pads needed truing and threading for the studs,etc. before valves, springs, rocker studs, push rod guide plates,valve seals ETC. could be installed.
IVE also seen heads that were basically ready for assembly as the came from the box!
A LOT of detailed questions need to be asked before going that route....
BUT ILL also point out that in many cases you'll save a great deal of money, not paying for parts that you won,t be using and get far better quality components, and be much surer the clearances are correct if you do it yourself with components you select.
you generally won,t get titanium retainers and valves that are .100"-.250" longer and the better quality beehive springs, or similar components and clearance work in an off the shelf cylinder head.
naturally it helps to start with a decent quality casting from a major manufacturer, so components are easily found that match the application.

these links contain a good deal of useful info

http://www.highperformancepontiac.com/t ... index.html

http://www.racingsprings.com/

viewtopic.php?f=52&t=528

viewtopic.php?f=52&t=1005

viewtopic.php?f=52&t=534

viewtopic.php?f=52&t=697

viewtopic.php?f=52&t=553

viewtopic.php?f=52&t=2875

viewtopic.php?f=52&t=319

viewtopic.php?f=52&t=240
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » August 14th, 2009, 9:51 am

first on the push rods, theres a huge difference between materials and tubing wall thickness between different manufacturers and part numbers, some 3/8" rods are stronger than SOME 7/16" push rods, wall thickness and materials used vary tremendously.

thick wall 4130 CHROMOLY push rods will be stronger than stock 1010 steel, many push rods have a .080 wall thickness, some a .083 , 0r .063 some heat treated, ETC., some are not even steel but carbon fiber, with titanium tips or all titanium.

you NEED to MEASURE clearances, and TEST valve springs never ASSUME anything on cylinder heads, and you got good advice concerning ALWAYS swap to decent MATCHING springs when installing a new cam if your not 100% sure of the spring rates and even then verify clearances



viewtopic.php?f=52&t=528

http://www.summitracing.com/parts/CCA-7942-16/

http://www.flatlanderracing.com/manpushrods.html

http://books.google.com/books?id=Ulvzvj ... ds&f=false

http://books.google.com/books?id=gsgQMT ... ds&f=false

http://cgi.ebay.com/ebaymotors/COMP-CAM ... .m20.l1116

http://www.summitracing.com/parts/CRN-13635-16/

http://www.paeco.com/Titanium%20Products.htm

http://www.mantonpushrods.com/Pushrod-Info.html

http://www.usaperform.com/cams-lifters- ... tml?page=1

Column Theory
Because a pushrod is an eccentrically loaded column due to angularity load and arc motion within the engines atmosphere, whenever possible, it is most proper to use either a single taper or offset dual taper design pushrod. It is also very important to use the largest diameter pushrod that you can fit in the engine. This will help lessen deflection in the pushrod by putting the major diameter and mass where it is needed the most. The greater the angularity, the greater the arc motion. As the pushrod encounters this, the high load area on the tube moves closer to the energy source. The energy source being the lifter, as it travels up the ramp of the camshaft. It makes it even more important to use these tapered designs when using large roller bearing diameters, increased valve lash, very high engine speeds, high rocker ratios, rapid valve train acceleration and high spring pressure. These tapered designs make it easier for the pushrod to do its job properly, and will enhance the performance of all the other valve train components, which will enable the engine to produce the maximum possible horsepower. The tapered designs and large diameters will also reduce valvetrain harmonics. Do not be over concerned about pushrod weight. The difference between a stock 5/16 diameter pushrod in a small block Chevrolet and a 7/16 to 3/8 tapered pushrod, represents a difference of approximately 2.5% of effective weight. This is because the pushrod is on the slow moving side of the valve train. The effective increase in weight between the two pushrods may be small but provides a huge increase in valve train stability. Remember the valve side of this valve train is the critical side where any weight savings will make marked improvements. No matter what we change, valve train stability is the goal.

Important Special Instructions & Suggestions
It is very important to determine proper pushrod length. Improper pushrod length can cause a number of problems including excessive valve guide wear, lessened valve lift, valve stem side thrust, coil bind, improper valve to piston clearance and also rockerarm to retainer interference (in some cases lash caps can be used to help correct rockerarm to retainer clearance problems).

Check the radius of the lifter receiver cup and rockerarm cup/ball before ordering to help prevent mistakes. Improper ordering may result in parts failure. Watch for variations from stock radius in aftermarket lifters.

Make sure significant oil volume reaches the rockerarm end of the pushrod to help prevent galling due to excessive heat generation and lack of lubrication. To prevent interrupted oil flow to the pushrod, it is very common and almost always necessary to modify the lifter body so oil flows through it no matter where it’s positioned in the lifter bore (call for details). Oil restriction in the engine block is not normally recommended.

When possible, try to use larger diameter pushrods to spread out the load and lower the stress on the tube. This will help lessen pushrod deflection. Heavy wall tubing is a good idea also, to minimize compression. Many problems occur when a pushrod is inadequate for the application.

In high RPM applications tapered pushrods are a must for the serious racers. Tapered designs help to dampen harmonics in the valve train; extended valve spring life and increased usable RPM will usually be noticed.

Do not allow over clearancing for the pushrod. This may cause the pushrod to move around or deflect more than needed. Clearance of .010 at the closest point, wherever that may be during its complete cycle is sufficient. The cylinder head and engine block can often be utilized like a big guide plate and dampening device, which stabilizes the pushrod. Just make sure that there is no interference problems when turning the engine over on the engine stand.

Tapered pushrods should not be used in guide plate applications. Improper clearance and interference problems are sure to occur. Use only straight tube pushrods, specifically surface hardened for guide plate use in this application. Note: See series #2 and #4 for guide plate applications.

If you are using a tool steel rockerarm adjusting screw, it is almost always suggested that a tool steel pushrod tip be used at the rockerarm end. This will ensure proper compatibility.

Note: When using Manton pushrods, adjustments to valve/cam timing, valve to piston clearance and fuel curve may be required.
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » December 15th, 2009, 4:09 pm

http://www.arp-bolts.com/Catalog/Catalo ... g_0046.pdf

rocker studs must match the applications (chart above)
and youll want to keep in mind that you don,t just screw them into the heads without verifying
several factors,
for example
Image
verify
the studs thread diam.,
thread pitch,(metric?, SAE?)
the depth of the threads in the heads,
the specific torque suggested,
if sealant is required on the heads,
is a pushrod guide plate required?
Image
have you used a clean/out or thread chaser?
you'll, need to verify the studs don,t bottom out or they can crack the heads!
you'll need to verify the rockers,used have both a slot length and diam.that allows the stud not to bind at both ends of its arc!
you'll want to verify the poly locks match the rocker slot for clearance and remember the stud that goes thru the rockers axle must have the rounded side of that axle facing down and the flat side of the axle facing up so the poly lock shoulder snugs up squarely on the rockers axle

Image .theres a threaded internal jam or locking stud inside the poly lock thats adjusted and tightened with a hex or Allen key, that lock stud needs to be backed out as far as it can go before you adjust valves to get the poly locks to fully engage the rocker stud threads, THEN and only after you get the rocker geometry correct do you tighten the locking studs, to approximately there final location.

its MANDATORY that you get the valve train geometry and clearances correct, if you bind or bend components your easily exerting hundreds if not thousands of pounds, of resistance/force on the effected components, and major bad results will almost always result in a very short time
if you bend a push rod or bust a rocker stud.........................STOP, and find out exactly what happened before you continue
btw the BEST aluminum rockers IVE ever used for GEN 1 SBC were ERSON BILLET ROLLER ROCKERS
PART # E928069 1.6:1 ratio for 3/8" studs
PART # E928072 1.6:1 ratio for 7/16" studs



http://www.erson-cams.com/pdf/Chevrolet.pdf

http://www.erson-cams.com/pdf/valvetrain.pdf

http://www.erson-cams.com/AskTechForm.aspx?brandId=7

IVE always prefered STEEL roller rockers over ALUMINUM for two reasons
first STEEL has a MUCH GREATER fatigue life under repeat stress than aluminum, and steel generally has far fewer clearance issures with other components, plus some STEEL roller rockers are REBUILDABLE

http://store.summitracing.com/partdetail.asp?part=CCA%2D1302%2D16&autoview=sku

http://www.enginebuildermag.com/Article ... itch_.aspx


http://store.summitracing.com/partdetail.asp?part=CRN%2D11600%2D1&autoview=sku

in MOST cases you can install 1.6:1 roller rockers with MINOR machine work, (I have seen on rare occasions no machine work necessary)
but in any case its easily done,

the tool comes with instuctions

http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO%2D66485&N=700+115&autoview=sku

and before a dozen guys start telling you they installed them with zero problems on stock heads, keep in mind most guys don,t take the time to check ALL the clearances thru THE FULL rotation of the rockers arc. and it they don,t break or bind parts ,THEY assume its fine
but the truth is the pushrod should NEVER touch either end of the slot even lightly anywhere in the arc.
I get questions all the time about roller rockers,"are they worth it?" "do they really help?"etc.
if they are correctly installed on a mild sbc and especially if the higher 1.6:1 ratio is used they tend to help on a mild cam as they tend to both reduce friction and increase effective flow rates,15-20 hp gains in the higher rpms are fairly common swapping from stock rockers.
on a well built performance application they are almost mandatory, because they reduce heat, are far more precisely made and lower friction

http://www.compcams.com/Community/Articles/Details.asp?ID=153327675

http://www.compcams.com/Community/Articles/Details.asp?ID=-1966802678

http://www.vetteweb.com/tech/vemp_0703_corvette_rocker_arms/index.html

http://www.compcams.com/information/Products/rockerArms/ProMagnum.asp
more info


http://www.centuryperformance.com/valveadjustment.asp

http://www.vetteweb.com/tech/0204vet_small_block_rocker_arms_ratio/index.html

read thru this it points out some of the potential gains and problems with swapping ratios

It may surprise many people but even many corvettes came with pressed in rocker studs, the fastest way to visually verify is to look for the hex stud base thats used to screw them in, if theres no hex base chances are excellent that they are press in studs.
Image
typical pressed studs

Image
screw in rocker studs

Image
http://www.summitracing.com/parts/BRO-BR1230/?rtype=10
Image

STUD GIRDLES ADD A GREAT DEAL OF RIGIDITY TO THE VALVE TRAIN
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
grumpyvette

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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » January 16th, 2010, 8:21 pm

http://www.enginebuildermag.com/Article ... locks.aspx

some of the least expensive sbc roller rockers Ive found, now I don,t have any long term experience yet with these but I doubt summit will put their name on TOTAL CRAP, so theres a good chance these will work fairly well

http://www.summitracing.com/parts/SUM-G6936-16/


IVE USED ERSONS EXTREME DUTY ROLLER ROCKERS IN MANY ENGINES OVER MANY YEARS WITH COMPLETE SATISFACTION (notice those are NOT the standard roller rockers they sell)

http://www.pbm-erson.com/store.php?catId=481&parent=24

http://www.usaperform.com/extreme-duty- ... p-849.html
Image


while your checking your valve train, check for weak or broken valve springs, more than one guys has broken a valve spring and wondered why the car runs like crap after entering valve float a few times, if you catch it early you may prevent dropping a valve and a huge expensive repair bill.

Image
Image
Image
Image
Image

Image

BEEHIVE SPRINGS and FORGED STEEL ROCKERS GIVE A GOOD DEAL MORE ROCKER TO RETAINER CLEARANCE
Image

read thru these threads and sub linked info

http://www.aa1car.com/library/valve_spr ... gnosis.htm

viewtopic.php?f=50&t=903&p=10020&hilit=rope+adapter#p10020

http://www.carcraft.com/howto/ccrp_0801 ... index.html

viewtopic.php?f=52&t=181&p=7156&hilit=springs+beehive#p7156

viewtopic.php?f=52&t=1716&p=4248&hilit=+beehive+spring#p4248

viewtopic.php?f=52&t=3124&p=9141&hilit=+beehive+spring#p9141

viewtopic.php?f=52&t=663&p=911&hilit=+rockers+girdle#p911

viewtopic.php?f=52&t=401&p=8370&hilit=vortec+heads#p8370

http://sbftech.com/index.php/topic,15607.0.html
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
grumpyvette

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Re: sellecting valve springs, and setting up the valve train

Postby grumpyvette » January 16th, 2010, 8:22 pm

http://www.enginebuildermag.com/Article ... locks.aspx


High Performance Rocker Arms, Valve Springs, Retainers and Locks


By Larry Carley

Larry Carley

Upper valvetrain components have more of an effect on power and reliability than you might realize. Most engine builders know that changing the rocker arm ratio increases valve lift for more power. But did you know that changing the rocker arm pivot point can also reduce friction and the rate at which the valves open and close?

On a small block Chevy, altering the rocker arm geometry without changing the rocker arm lift ratio can add 15 to 20 horsepower at the rear wheels.

The stock lift ratio for a small block (SB) Chevy V8 rocker arm is 1.5:1, and for a big block (BB) Chevy V8, the ratio is 1.7:1. Bolt-on aftermarket high lift rocker arms with higher ratios are often used to get more net lift out of an existing cam profile. The most common high lift ratio upgrade for a SB Chevy engine is 1.6:1 rocker arms, and 1.8:1 rockers for BB Chevys. But some performance rockers now offer ratios as high as 2.0:1 or even higher!

Increasing the lift ratio adds horsepower with little or no loss in low rpm torque, idle quality or vacuum. By opening and closing the valves at a faster rate, the engine flows more air for the same number of degrees of valve duration. High lift rocker arms also reduce the amount of lifter travel needed to open the valves, which reduces friction and the inertia of the lifters and pushrods that must be overcome by the valve springs to close the valves. On the other hand, increasing the rocker ratio also increases the effort required to open the valves because of the leverage effect. The higher the rocker arm ratio, the greater the force the camshaft, lifters and pushrods have to exert to push the valves open. But when the valves close, the increased leverage of the rocker arms works the other way making it easier for the springs to shut the valves and push the rocker arms, pushrods and lifters back to their rest positions.

On SB Chevy engines, the stock stud-mounted rocker arms are supposed to be self-centering and self-aligning. The ball pivot inside the stamped steel rocker arm allows the tip of the rocker arm to follow the top of the valve as the valve is pushed open. This creates some back and forth scrubbing friction between the tip of the rocker arm and the top of the valve. And the higher the valve lift and the stiffer the springs, the greater the friction. Over time, this can cause side wear in the valve guides, tip wear on the end of the valve stems, and worn rocker arms.

Aftermarket performance rocker arms, whether they are stamped steel, stainless steel, or diecast, extruded or machined aluminum, usually have a roller tip to reduce friction between the rocker arm and valve. The roller, in theory, rolls back and forth on the top of the valve stem to reduce friction, wear and side forces exerted against the valve. Most stud-mounted aluminum rocker arms also have a needle bearing fulcrum to further reduce friction at the pivot point, and a hardened steel insert in the short end of the arm to accommodate the pushrod. Power gains of 15 to 30 horsepower are often claimed for aftermarket rocker arms even with stock ratios because of reduced friction. Aftermarket performance rocker arms are also stronger than stock stamped steel rocker arms, and provide improved reliability and longevity. But stud-mounted rockers have certain limitations.

One is that they often require pushrod guide plates to help keep everything in proper alignment, especially at high rpms and spring loads. Another limitation is that they can't handle valvetrain misalignment very well. If the rocker arm twists, it may bend the pushrod and/or allow the tip of the rocker arm to walk off the side the valve tip. If that happens, the rocker may push down on the retainer instead of the valve, causing the locks to pop out and the valve to disappear down the guide, destroying the engine.

SHAFT MOUNTED ROCKERS
The hot setup today is shaft-mounted rocker arms. Shaft mounted rockers would seem to be a throwback to the days before the first stud-mounted stamped steel rocker arms appeared on small block Chevy V8s in 1955. One of the features that made the SB Chevy such a performer was its lightweight, high revving valvetrain. But keep in mind, that was a time when maximum engine speeds were in the 6,500 to 7,000 rpm range, not 8,500 to 9,000 rpm or higher, and most engines were running single springs, not double or even triple springs.

Shaft mounted rockers have a number of advantages. One is better alignment. The shaft is rigid so the rockers are held in perfect alignment. This eliminates the need for separate pushrod guide plates while also limiting valve train deflection. At high rpm, pushrods and rocker arm studs can flex quite a bit, and the more they deflect the more it hurts valve lift, duration and valve control. This costs horsepower and can be seen on a dyno. So the more rigid the valvetrain, the less the valve flutter at high rpm. Shaft mounted rocker arms also provide extra strength and support, eliminating the need for a separate stud girdle. Aluminum stud girdles are often necessary to reinforce the valvetrain when a high lift cam (or rockers) and stiff springs are used. The girdle clamps around the studs and ties them together to reduce stud flex and the risk of breakage. But the girdle also makes it harder to adjust the valves. Shaft mounted rocker arms don't have that issue because the adjusters are on the arms, not the studs, and are easily accessible.

Mounting the rocker arms on a rigid shaft also eliminates the "jack hammer" effect that occurs with stud-mounted rockers. Every time the valve opens and closes, the change in valve lash that occurs with a solid lifter cam causes a stud-mounted rocker arm to slide up and down on its stud. This hammering effect can pull a pressed-in stud out of the cylinder head, and may cause fatigue failure in a screw-in stud or the rocker arm.

Another advantage of shaft-mounted rockers is better geometry. By lowering the pivot point of the rockers slightly with respect to the valves and pushrods, the arc that the tip of the arm follows is moved further down the curve. This reduces the back and forth scrubbing on the top of the valve, which reduces friction even more. One supplier of shaft-mounted rockers says this change alone reduces the torque it takes to turn a SB Chevy over by 80 ft. lbs, and is good for 15 to 20 horsepower.

Lubrication can also be an advantage with shaft-mounted rockers. Some have internal oil passages that route pressurized oil directly to the rocker arms and/or valve springs instead of relying on splash lubrication from oil squirting up through the pushrods. Shaft mounted rockers are available from a number of aftermarket suppliers, and fit not only stock SB Chevy and Ford heads but also most of the popular aftermarket heads made by Brodix, World, Edelbrock and others. The shaft-mounted rockers typically sell in the $700 to $900 range and are an excellent upgrade for any performance engine.

Another supplier of aftermarket rocker arms has taken a similar approach by redesigning some of their stud-mounted rocker arms for the LS1 Chevy. The rocker arms require milling the stud pads on the cylinder heads .170" to accommodate the lowered rockers, but the net result is better geometry, less side wear on the valves and faster initial opening that produces more horsepower.

What you may not know is that the actual ratio at which a rocker arm opens a valve is not constant, but varies as the valve opens and closes depending on the arc the arm travels and the position of the rocker pivot point with respect to the top of the valve and the pushrod. The stock LS1 rockers are mounted rather high and initially open the valve at a rate equivalent to about 1.54 to 1 before eventually reaching 1.7:1. The quick lifting aftermarket rocker arms, by comparison, lift the valve off the seat at a ratio that is closer to 1.8 to 1 and then goes to 1.7 to 1 at .200" valve lift. This has the same effect as increasing valve duration about six degrees, and produces 15 to 18 more horsepower.

INTERFERENCE ISSUES
As the ratio of the rocker arms goes up, the net lift of the valves increase and the valve springs are compressed much closer together. Clearances must be checked to avoid coil bind and contact between the bottom of the valve retainer and top of the valve guide. Springs should have a safety margin of .060" of remaining travel at maximum valve lift to avoid coil bind. The minimum clearance between the retainer and valve guide at maximum valve lift should also be .060". If the minimum clearances are not maintained and the valve spring or retainer bottoms out, the valvetrain will usually bend or break a pushrod. Clearance between the rocker arm and spring retainer must also be checked at maximum lift to make sure they don't touch. The stock rockers on a SB Chevy V8 can handle about .470" of valve lift. More lift requires switching to "long slot" rockers or aftermarket rockers with extra clearance.

High lift aftermarket rocker arms or a high lift cam may require using different springs that allow increased spring travel. Some springs cannot handle a maximum valve lift of more than .550". For higher lifts, different springs are required. Follow the spring supplier's recommendations when matching valve springs to maximum valve lift. Another way to avoid spring bind is to raise the installed height of the valve or to lower the spring seat. But both of these will reduce spring tension, which is not the way to go with a high revving engine.

For small block street performance engines with a flat tappet cam and no more than .450" of lift, single springs with 80 to 90 lbs. of seat pressure with the valves closed are usually adequate. For street/strip performance engines, springs with 100 to 120 lbs. of seat pressure are usually recommended. For street hydraulic roller cams, seat pressure should typically be 105 to 140 lbs., and should not exceed a maximum of 150 lbs. with a mechanical roller cam.

Double or even triple springs are usually required to achieve higher spring pressures. Seat pressures for double springs typically range from 130 to 150 lbs. or higher, and 300 or more lbs. for triple springs. Most NASCAR teams run dual springs with seat pressures of 190 to 200 lbs. and open pressures of 500 to 600 lbs. at .750" lift. Pro Stock drag racers, by comparison, typically run triple springs with seat pressures of 375 to 475 lbs. with the valves closed, and up to 1,000 lbs. open!

Increasing spring pressure increases the rpm and horsepower potential of the engine. Every additional 100 rpm may be worth an extra 20 or more horsepower on a highly modified performance motor. The current limit for steel valve springs is about 83 to 85 cycles per second, or about 10,000 rpm. NASCAR teams run a 200 to 400 mile race at 8,500 to 9,000 rpm. But drag racers only run a quarter of a mile.

High pressure valve springs can deliver the rpms, but there's a price to be paid because the springs don't last. Running at such high rpm wears out the springs. Consequently, the springs have to be replaced fairly often (every race with NASCAR engines, and after so many runs with drag racers).

Higher spring pressures also puts more load on the rocker arms, pushrods, lifters and cam lobes, which increases the risk of something breaking.

According to one major camshaft supplier, standard camshafts can usually handle open valve spring pressures of up to 550 lbs. But for higher spring pressures, a carburized 8620 or 9310 steel camshaft is required.

Installing double springs may require the following modifications:

*
* Flycutting the spring seats in the heads to accept the springs.
* Changing the spring retainers to ones that are designed for double or triple springs.
* Changing the valve seals and/or machining the guides for extra clearance.
* Replacing pressed-in rocker arm studs with screw-in studs and a stud girdle, or installing shaft-mounted rocker arms.
* Replacing the stock pushrods with stronger and stiffer 4130 chrome moly pushrods (to prevent pushrod flexing and breakage).
If the springs provide more than 350 lbs. of pressure when the valves are open, the stock stamped steel rockers will have to be replaced with stronger aftermarket steel or aluminum rockers.



BEEHIVE SPRINGS
Beehive springs that taper towards the top are a hot commodity in the aftermarket, but date back to the earliest days of the automobile. Like shaft-mounted rockers, though, they are finding new applications in todays high performance engines. Chevy LS1/LS7 series engines use a factory beehive spring, as do Ford modular 4.6L V8s. Similar spring designs have been developed for SB Chevy and Ford engines by aftermarket suppliers. Unlike a conventional valve spring that has a constant diameter, a beehive spring tapers in toward the top sort of like a real beehive (thus the name). A smaller top means a smaller and lighter valve spring retainer can be used to reduce weight. Also, the change in the diameter of the spring as it tapers toward the top creates a progressive spring rate that helps the spring resist harmonics that occur in conventional constant rate springs. The bottom line is that beehive springs perform better than conventional single springs on many (but not all) engine applications.

One spring supplier said their beehive springs can increase the rpm potential of an engine 100 to 1,200 rpm depending on the cam, valvetrain and other engine modifications. The maximum amount of valve lift a beehive spring can handle is about .650", so if the engine needs more lift it will require dual or triple springs.

Beehive springs have been popular on the street, but some racers are cautious about using them because there's no safety margin if a spring breaks. With a double or triple spring, the engine won't eat a valve if a spring breaks. The extra springs serve as a backup to pull the valve shut.

SPRING COATINGS
Heat is the main enemy of the springs, with dual and triple springs typically generating more heat than single springs because they rub against each other. Managing heat, therefore, is critical for spring longevity.

The durability of a spring depends on the quality and purity of the alloy that is used to manufacture the spring, the heat treatment the spring receives, and any additional surface treatments the spring is given. Some springs are nitrited while others are coated with proprietary chemicals that help the spring run cooler. Another trick that can extend spring life is to have the springs cryogenically treated. Freezing the springs to 300 degrees below zero can increase spring life up to five-fold, according to those who do it.

SPRING INSTALLATION
There are a couple of things to watch when installing valve springs. One is height. This ensures the springs have the required pressure to keep the valves shut. Height is checked by measuring the distance between the spring seat in the head and the retainer on the valve stem. Most performance valve springs are closely matched, but if adjustments are needed it can be done by shimming the valves to equalize pressures. The thicker the shim, the more it increases spring pressure. Don't overshim, though, because doing so may lead to coil bind with a high lift cam or rocker arms.

Shims are made of hardened steel, come in various thicknesses and are usually serrated on one side to prevent rotation (the serrated side faces the head). Some shims are also designed to help insulate the springs from heat generated by the cylinder head. Springs should also be lubricated when they are installed in a new engine, especially double and triple springs, to reduce friction. Soaking the springs in oil or coating them with assembly lube should provide adequate protection during the critical first start-up.

VALVE SPRING RETAINERS & LOCKS
Reducing weight on the valve side of the rocker arm has more of an impact than reducing weight on the pushrod side because of the leverage effect. Lightweight valve retainers made of titanium have long been the preferred upgrade here. But in the past year, the price of titanium has skyrocketed. Most of the world's titanium supply comes from Russia and is being consumed by China. Some aftermarket suppliers have responded to the changing market conditions by introducing new lightweight steel retainers.

For street applications, steel retainers with stock 7 degree locks are usually recommended. But for racing or high rpm roller cams, titanium retainers with 7 or 10 degree locks can reduce weight. Some locks have an extra step inside that reinforces the bottom of the retainer and reduces the risk of the valve pulling through at high rpm. When the valve locks are installed around the valve stem, their edges must not touch each other. They should clamp against the valve stem and hold it securely. Keep in mind that the design of the retainer affects the installed valve height and spring tension.
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
grumpyvette

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