383 building advice



Re: 383 building advice

Postby Indycars » November 22nd, 2014, 10:17 am


Below is the Cam Manager window. Using the 1.6 rockers add a tiny bit of
duration to the Crower 00471 camshaft.

CamManager_Crower_00471.JPG


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Re: 383 building advice

Postby cornor » November 22nd, 2014, 11:08 am

Hello again, and thank you and for taking the time to guide me and advice me . I am trying to absorb and learn, but obviously have a way to go :).
Thank you Phil for pointing me to Rick excellent instruction on port matching, I read through this when I read the engine tread, which I general is packed with very good and useful information for a guy like me with limited knowledge and experience with engine building. I will use the airgap intake, and try to port match it as per the good guideline I have from Rick :)

Here is the calculation I did, I also tried the same with the compression calculation sheet you have Rick, but was a bit uncertain on some input, so I used this one from United Engine & Machine who make the Icon pistons. I could possible use a thinner head gasket 0.015 maybe and raise the compression 0,5, but I already have the felpro 1003 gaskets which AFR recommend and they are 0,041 thick.

I have 7/16" studs; and I will consider if it is worth taking any risk with unknown brand rockers.

John, The springs I have is the AFR- PAC Racing Spring 1.290" OD Hydraulic Roller Dual Valve Spring,
140 lbs on seat, .600" maximum lift, Max RPM 6300-6800 which came with the heads. I understand that I might have to change these.

Thank you for the very interesting and detailed report on the on the engine with the Crower cam, Rick, I will spend some time reviewing this, but from what I can see I like the torque and power curves and the numbers that this indicated.

I have the engine at the machine shop now, and waiting for the 4.040 pistons which has been ordered, then I will decide if bring the engine home and work on putting it together myself or get the shop to put together the long block, and the assemble the cam and head myself at my home.

I am preparing to take out the other engine from the corvette now, to clean up the engine bay, and make everything nice to put in a new engine. I am calculation the number to see if I can afford to put in a Tremec 5 speed at the same time, but cost keep adding up, with new cam, intake +++, so I will have to see.

I will keep you posted and possible add some pictures when I get things going.

Thanks again all of you for great input and support.

Regards Pal ( it is actually Pål which would be pronounce Paul) But we have a special Norwegian letter "å" :)

compression-calculation2.jpg
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Re: 383 building advice

Postby Indycars » November 22nd, 2014, 1:09 pm

cornor wrote:( 1 ) Here is the calculation I did, I also tried the same with the
compression calculation sheet you have Rick, but was a bit uncertain on some input,
so I used this one from United Engine & Machine who make the Icon pistons.

( 2 ) I could possible use a thinner head gasket 0.015 maybe and
raise the compression 0,5, but I already have the felpro 1003 gaskets which AFR
recommend and they are 0,041 thick.

( 3 ) Thank you for the very interesting and detailed report on the
on the engine with the Crower cam, Rick, I will spend some time reviewing this, but
from what I can see I like the torque and power curves and the numbers that this indicated.

( 4 ) I have the engine at the machine shop now, and waiting for
the 4.040 pistons which has been ordered, then I will decide if bring the engine home
and work on putting it together myself or get the shop to put together the long block,
and the assemble the cam and head myself at my home.

Regards Pal ( it is actually Pål which would be pronounce Paul) But we have a special
Norwegian letter "å" :)

compression-calculation2.jpg



1) The DCR you calculated is correct according to the United Engine's instructions,
but the estimated IVC is off by quit abit. It's always better to use real number when
you have them. The cam card tells you that the intake valve closes at 69° ABDC.
This number must be the seat timing number and not at .050 inches. Now when we
use the correct timing number you get a much lower DCR with the 10° later IVC angle.

I bet the numbers that you were confused about were the two numbers, "Top Ring Height"
and "Ring Land to Cyl Bore Clearance". They make very little difference and can be
ignored if you don't know them, the numbers I used should be close enough. If you check
out the "Compression Ring Volume" on the page 3 (Intermediate Calc) you will see that
it only amounts to .25 CC's. Technically, it's all part of the combustion chamber volume.
It's just me, I like to calculate down to the Nat's Ass.

Somehow you need to reduce to combustion chamber volume by about 5 CC's, then you
will have a DCR of ~~ 8.0

DCR_CalcsWithCrower00471.JPG

Crower_HR_00471_555_560.JPG


2) NO, please don't do that!!!

Your quench distance will be much too low at .001 + .015 = .016 inches. This needs to
be in the .038 to .045 range, preferably .040-.042 inches.

Quench01.jpg


3) You are very welcome, but remember ...... that the OUTPUT numbers are no good
until YOU confirm that the INPUT numbers are correct !!!!!!!!

4) Please bring it home, your expenses at the machine will be much higher if you have
them do ALL THE REQUIRED CHECKS, plus assemble it. Doing it yourself will bring a
great deal of satisfaction for yourself. We love helping here on this forum and like to
think we have the friendliest people.

Hey thanks for the heads up about your name and pronunciation! That makes more
sense now.

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Re: 383 building advice

Postby cornor » November 23rd, 2014, 9:01 am

Rick, thanks again for good input. I though I had the DCR close too 8, but obviously the calculation used was not accurate enough. Will 7.7 visa 8 make a big difference for the performance of the engine ?. If so I will have to consider my options. From AFR web page they inform that milling 0.006 will reduce volume approx 1cc, so I could mill off around 0.030" to reduce 5cc and obtain 70cc combustion cambers. Alternatively If I used another cam which have a lower intake valve closing angle that would also raise the DCR, if I get this right. I tried put in numbers for a cam from Lunati specked by David Vizard in his book " David Vizard's How to Build Max Performance Chevy Small Blocks on a Budget" advertised duration 282/282 and 231/231 deg at .0.050 and LSA 106 it will come out quite good on the DCR, but I do not know if that could be a option which will give me a good result without modifying the heads , or will I be loosing a lot of power with such a set up ?. I see Vizard advice a LSA like 106 for a 383 but I am not sure if this will have big impact on idle quality, he state that as long as the overlap is not too much you should not have problems. I have added the info from the book about the cam into your comp calc. spreadsheet i get:

Advertised Duration: 282 / 282
with Total Cam Adv: 4
LSA/ICL 106/102

Intake Open BTDC: 39
Intake Close ABDC: 63
Exhaust Open BBDC: 71
Exhaust Close ATDC: 31
Overlap: 70

Any suggestion on which way to go, mill down the head (to get DCR of 8) or leave as is, or possible change cam and keep the rest of my set up as is ? Please excuse me if I ask a lot of stupid questions, but I am not a experienced engine builder, and just trying to learn and avoid doing mistakes as I plan and move forward with my building. Ideally it may have been better to start from scratch, but as I already have a lot of parts available, I would like to use they if suitable. Thank you for your help and patients with me. :)

Regards
Pal
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Re: 383 building advice

Postby grumpyvette » November 23rd, 2014, 10:33 am

I'd suggest you don,t mill the heads as its potentially going to add far more problems that it cures.
ideally youll want a fairly tight LSA of close to 106 in a cam for a 383, but the difference between a 106-to a- 110 LSA,is not going to make or brake the combo, it simply changes the volumetric efficiency slightly and its only ONE of dozens of factors that will effect your results.
going with a slightly wider LSA tends to broaden the power band and smooth out the idle SLIGHTLY but the difference is not huge on cams with the same lift and duration.
yes the more factors that you calculate and take the time to maximize the better, but don,t think that one change will destroy the engines power curve.
I tried the CROWER 00471 in my cars 383 and then settled on the CRANE 119661, there was no question the crower 00471 made better peak power, than the crane 119661 , but being a bit older and less impressed with "POWER" than over all day to day drive-ability, and having installed a 200 hp wet nitrous system on that car that provided more than enough EXTRA kick when I needed it I felt I could compromise and loose a few PEAK N/A hp with ZERO NET LOSS
every choice you make is a compromise in some area!, ID strongly suggest you talk to at least 5 cam manufacturers and get their opinions on what cam to use, in YOUR application, then take that info, average the results in LSA,LIFT AND DURATION, and BUY the cam that best matches that AVERAGE and NEVER discuss with any cam manufacturer what a different supplier might have recommended, simply, give them all the factors in the engine and drive train and let them make a choice, if you relate what others have said your skuew the results, and in most cases guys seem to want larger cam duration that the engines ideal cam might have, remember insisting on bigger,or longer spec, in a cam duration, is rarely going to result in a better, running engine ,in a street car cam selection, once you get into the correct ball park in lift and duration.
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Re: 383 building advice

Postby Indycars » November 23rd, 2014, 12:34 pm


Taking off .030 inches is a lot for the sake of reducing chamber size. It would
tend to reduce the clamping for between the head bolts by reducing the strength
of the head. That's not to say it wouldn't work, but the chances of getting into
trouble are little greater.

Look, you don't need to apologize for your questions!!! We love to help and encourage
all questions, it gives us old guys something to do. As long as you are learning and
not making the SAME mistakes twice, then you should be proud of your progress!!!

If you can be happy with the engine you finally build, then by all means use the parts
you have. But it's best to start over, if you are going to spend lots of money and
time and get to the end and be disappointed with the results.

Rick
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Re: 383 building advice

Postby cornor » November 30th, 2014, 4:29 pm

Hello again, Been busy with work, but have checked around for alternative cams
I got a proposal from Crane for a #119701 HR cam. I also got some info from
Jones Cam who proposed

Cam# SBCR, HR70340-71340-108
224/228 @ .050"
.340"/.340" Lobe Lift
.544"/.544" Valve Lift
108 LSA

Duration Lobe Net Lifts
Part # @ .006″ @ .050″ @ .200″ Lift 1.5 1.6 1.7
EHR70340 272° 224° 147° .340″ .510″ .544″ .578″
EHR71340 276° 228° 151° .340″ .510″ .544″ .578″

I don't know how these would work in my engine, but the Jones cam came out with exactly 8 in DCR when I put in the no. in the calculation.
Both of these cams have lower duration and lift than the Crower and Crane 119661, so I assume this give give me less power up top but possible some better torque down low ?.
Jones decribe the cam "This cam was designed to make peak HP at 5,500, and will make great low-end and mid-range power. It'll also hold the power past 6,000rpm." estimated power level 450-500hp.

I have sent inquiries to some other companies like Crower, Lunati, Comp Cam and Isky- but they have not replied.

Any comment on these cams ? Do you think they would be worth considering ?
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Re: 383 building advice

Postby Indycars » November 30th, 2014, 7:25 pm


Looks like this is one of those Crane cams with a Asymmetrical Lobe profiles. They
like to accelerate the valve open faster than they decelerate it closed, which helps
keeps the valve from bouncing off the seat when it closes. So you can't make the
usual calculations like you can with a symmetrical lobe. Crane has to give you the
numbers.

The Hydraulic Intensity (HI) 48 of the Jones cam shows a cam that open/closes the
valve faster and give better performance by creating more area under the curve.
BUT it will be harder on the valve train when compared to the Crane HI of 66 cam.
I don't know what is an acceptable HI number for the street, hopefully Grumpy will
speak up on this matter.

The graphic below show the difference in different types of camshafts, but the
concept is the same ...... more area under the curve means better performance.

Fig5LiftCurve_HydSolidRoller800.jpg


Because of the asymmetrical lobe, I can't tell you if the cam is installed straight up
or 4° advance etc. If my numbers are correct, then the Crane is going to have a
cranking pressure that is too low to provide good torque at low RPM.

DCR Jones vs Crane 119071.JPG

Crane_HR_119701_518_539.JPG


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Re: 383 building advice

Postby cornor » December 2nd, 2014, 4:42 pm

Thank you Rick for good and valuable input.

I am wondering about the Hydraulic Intensity of 48, is this a high no.? As the Crower 00471 has 50, I wonder if these 2 deg. make a large difference ?.
What I can see is that the Jones cam come out at 8 i DCR and with my limited knowledge it seems that it could be a interesting choice. Would be very interested to hear if Grumpy have some comment to this cam, and if it could be a good alternative for my engine.

From what I can see the figures for advertised duration for the crane cam is at @.04", and if I have understood it correctly these figures can not be used directly into the table for dynamic compression, or am I wrong on this ? I think I read that you need to subtract some degrees to get the figure for @.06 and use this figure.
I read somewhere that a good estimate of the duration @ .006" will be 275° in and 283° ex. for this cam, but I have sent a email to Crane to check.

I also got a reply from Howard cams today and they proposed a 111145-10, which I have attached spec for.

I will check some more and hopefully learn some more on my way.

Regards

Pal
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Re: 383 building advice

Postby Indycars » December 2nd, 2014, 8:23 pm

cornor wrote:(1.) Thank you Rick for good and valuable input.

(2.) I am wondering about the Hydraulic Intensity of 48, is this a high no.? As the Crower 00471 has 50, I wonder if these 2 deg. make a large difference ?.

What I can see is that the Jones cam come out at 8 i DCR and with my limited knowledge it seems that it could be a interesting choice. Would be very interested to hear if Grumpy have some comment to this cam, and if it could be a good alternative for my engine.

(3.) From what I can see the figures for advertised duration for the crane cam is at @.04", and if I have understood it correctly these figures can not be used directly into the table for dynamic compression, or am I wrong on this ? I think I read that you need to subtract some degrees to get the figure for @.06 and use this figure.
I read somewhere that a good estimate of the duration @ .006" will be 275° in and 283° ex. for this cam, but I have sent a email to Crane to check.

(4.) I also got a reply from Howard cams today and they proposed a 111145-10, which I have attached spec for.

I will check some more and hopefully learn some more on my way.

Regards

Pal


1.) You are most welcome, it's enjoyable just helping!

2.) I think I asked Grumpy to comment on this last time, since I don't have tons of
experience with these numbers. I can calculate them, but then I'm lost when it
comes to helping someone else. I don't want to speak about something that I don't
direct experience with.

3.) If they give you a closing number at advertized duration, then use that, it's
the best you are going to get. It's usually quoted at .004 or .006 inches of lift. Your
number @.04" is actually .040 or forty thousands lift. Maybe you just left out a zero.
The only estimate I've seen is by Grumpy ...... add 15° to the duration @.050 inches.

You lost me when you stated @.06, I've not seen that number used for anything
camshaft related. I've not seen an estimate based on .006 and add 8°, this is usually
used as a closing number and can be used for DCR directly.

4.) It will be tomorrow before I can take a look at the Howard cam ..... this is so
much fun. I only hope you are enjoying the conversation.

Rick
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Re: 383 building advice

Postby grumpyvette » December 3rd, 2014, 8:56 am

guys , keep in mind this is NOT an exact BLACK and WHITE OFF or ON point your looking to hit, as you select components in a build, that allows you to achieve the ideal combo, its more like a SERIES of DOZENS of OVER LAPPING BELL CURVES ,EACH CHOICE IS A COMPROMISE in some area,yes you can make intelligent well informed choices to maximize your results but don,t think small mistakes or perfect choices will totally ruin or make a combo far better than anyone elses, its the combination, generally not a single choice (UNLESS ITS SPECTACULARLY BAD) that makes or breaks the final results theres dozens of choices to be made and each has a sweet point that will vary depending on the choices made with the other components selected, EACH CHOICE WILL EFFECT THE RESULTS YOU GET WITH THE OTHER CHOICES ,YES, YOU CAN MAXIMIZE YOUR RESULTS BY TRYING TO GET AS CLOSE TO THE PEAK ON EACH CURVE AS YOU CAN BUT SOME CHOICES WILL NECESSARILY NEGATE THE BEST SELECTION ON OTHER CHOICES.
ID also point out that MOST ENGINE DYNO PREDICTIVE SOFT WARE IS NOTORIOUS FOR PRODUCING LESS THAN REALISTIC RESULTS < AND WHILE ITS USEFUL ITS HARDLY RELIABLE, AS TO PREDICTING ABSOLUTE POWER/TORQUE NUMBERS AT ANY RPM RANGE

Image
COMPRESSION TO REQUIRED FUEL OCTANE
Image
FUEL OCTANE REQUIRED FOR CYLINDER HEAT LEVELS
Image
EXHAUST SCAVENGING EFFICIENCY
Image
THERMAL LOSSES TO FRICTION AS RPM AND LOADS INCREASE
Image
OIL TEMPS TO LUBRICATION EFFICIENCY
Image
IGNITION ADVANCE CURVE
Image
COOLANT TEMPS VS COOLING EFFICIENCY
Image
AIR TEMP VS COMBUSTION EFFICIENCY
Image
QUENCH EFFICIENCY
Image
PORT FLOW VELOCITY
Image
PORT STALL SPEED
Image
VALVE CROSS SECTIONAL AREA TO CYLINDER VOLUME
ETC...ETC...ETC.

if you select a certain STATIC COMPRESSION, your limited to the fuel octane ratings you can use without getting into detonation
this also changes with the cylinder head temperature, quench, cam timing, overlap, cylinder scavenging, ignition advance, the finish or thermal barrier coatings on the piston and combustion chamber, oil temperature, coolant temperature fuel and air temperature, use of and combustion temp regulators like methanol/water mist injection, and a dozen other factors each one of which is going to effectively generate a bell curve of performance that over lays and effects the other factors its melded with.
you can look up info related to each listed factor above "and a dozen more" and try to select the best possible choice, but what you'll eventually realize is that its 100% impossible to maximize ALL the potential, related factors simultaneously.
In an ideal internal combustion 4 stroke engine there would be zero friction, the fuel would ignite instantly at TDC, produce ever increasing pressure from TDC to at least 145 degrees past TDC on the power stroke,at a rate just a bit below a realistic safety factor concerning the strength of the rotating assembly and burn completely leaving no residual emissions or ash and achieve near 100% efficiency with little heat,loss.
we currently use about 8:1 DYNAMIC compression as a target simple due to the crappy low octane pump fuel available currently in most areas to prevent engine damage



viewtopic.php?f=55&t=2718&p=41142&hilit=octane+calculate#p41142

viewtopic.php?f=52&t=4081&p=10861#p10861

http://victorylibrary.com/mopar/cam-tech-c.htm

viewtopic.php?f=50&t=9816&p=40642&hilit=detonation+damage#p40642

viewtopic.php?f=52&t=727
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Re: 383 building advice

Postby Indycars » December 3rd, 2014, 10:24 am

cornor wrote:I also got a reply from Howard cams today and they proposed a 111145-10, which I have attached spec for.

I will check some more and hopefully learn some more on my way.

Regards

Pal


The Howard cams operates at a lower RPM compared to the Crower 00471.

Compare_Crower00471_To_HowardCams111145-10.JPG


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Re: 383 building advice

Postby grumpyvette » December 3rd, 2014, 11:07 am

viewtopic.php?f=71&t=555&p=45747&hilit=when+shift#p45747

this is one of those cases where you look at the predicted dyno result and instantly think, wow! look at that difference Id be foolish not to select one cam vs the other , but are you really basing the decision, on the facts?
a great deal about how a car performs relates to its power to weight ratio and its drive train gearing, obviously you'll want to gear the car and select tires etc. to maximize performance in the area ,or under the operational conditions that are most important too you!, this will generally require some compromises in other areas.
this is also where an over drive transmission allows you to get most of the performance benefits in both areas. a 3.73:1 rear gear ratio certainly will allow you to operate in the upper rpm ranges to extract the desired power

the fact is, your more than likely not basing the decision on the correct data, think it thru, you don,t really care about the low rpm torque as long as is available in sufficient quantity to easily move the average 3000 lb car rather effortlessly ,if its geared correctly, and it generally takes less than 250 ft lbs of torque and 80 hp to drive around town at part throttle
keep in mind you don,t use the whole power band while racing nor do you use the same section of the power band while driving around town as you do while racing.
while racing you'll seldom have the rpms fall much below the engines torque peak if the cars geared correctly to maximize its power transfer potential and it will shift at rpm levels above the power peak so it falls back near the torque peak.
your current 4 speed has a 2.2 first gear ratio, a 5 speed you referred to has a 2.87:1 first gear ratio and a .64:1 OD ratio.
ideally the rear gear x the transmission first gear ratio will fall in the 10:1-10.5:1 range, with the muncie and that 3.73:1 rear gear you have a 8.2:1 which if further hurt by the TALL 31" tire size
the TEMEC 2.87:1 first gear x that 3.73 rear gear come out to a 10.7:1 which is about ideal with that tall 31" tire

http://www.summitracing.com/parts/awr-t ... /overview/

http://www.datsuns.com/Tech/whentoshift.htm

http://www.welltall.com/ymc/discovery/car/shiftpt.html

viewtopic.php?f=71&t=555

while driving for decent fuel economy youll rarely exceed 4000rpm
Image

notice the power curve used while racing would be rather different
Image
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Re: 383 building advice

Postby cornor » December 3rd, 2014, 6:50 pm

Thank you Grumpy and Rick for educating me :) . You have come up with so much interesting and useful information, and I really appreciate this. I understand that there is some many other factors to consider than only looking at the engines torque and power curve. My first impression looking at the Howard visa Crower curves was that the Howard would be a better cam for a street driven car, but then after considering the good inputs from Grumpy, this may not be so clear.

I will in the near future have to make some decision on what additional parts I shall purchase. If I buy a two peace timing cover, it will make it easier to change the cam in the car later, IF I end up with something that not work with my car and my driving style.

Thank you again and good night from Norway. Pal
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Re: 383 building advice

Postby Indycars » December 3rd, 2014, 7:41 pm


Grumpy,

It may not make a big difference in the concept you are explaining. When you
labeled the graph, the "Torque Peak" label seems to be pointing to the Howard
torque curve and the "Shift Here" seems to be pointing to the Crower HP curve.

Is this what you intended???

Rick
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Re: 383 building advice

Postby grumpyvette » December 4th, 2014, 7:52 am

I was not, really concerned with which cam particularly was being targeted, I was pointing out that on a 383, your generally limited with a hydraulic valve train and piston speed limitations to about 6400-6500 rpm as an upper rpm limit if long term durability is a reasonable concern, (and shifting at 6300rpm sure won,t hurt durability) and what I'm saying is you generally shift at or a bit over the engines power peak and keeping in firmly in mind the limitations imposed by piston speed and valve train limitations, and ideally shifting so your falling back at or near the torque peak, (usually and Id say, ideally ,just a bit lower in the rpm band), this will generally produce the most consistent and highest average useful power and torque applied to the driving wheels to propel the car.
that milder Howards cam potentially has a good deal more lower rpm torque, than the Crower cam its being compared to, (according to the software dyno prediction) below 4000rpm but thats almost an illusion in one respect, and heres why,if you installed both cams in the car separately and test drove them you would without doubt notice the milder cam produced a bit more low rpm response and was easier to drive accelerating at part throttle, but once you decide to accelerate briskly and open the throttle , what happens? your engine rpms rapidly increase as the engine takes advantage of the now available increase in air flow, remember you control the engine rpm by RESTRICTING OR STRANGLING THE AVAILABLE AIR FLOW AVAILABLE, so at part throttle that mild cam takes full advantage of what,limited air flow is available, but once you make a good deal more air flow available, it can no longer keep up, its not lifting the valves high and long enough to allow nearly the same air flow as the slightly more aggressive longer duration Crower cam, thus once the RPMS have increased , and your demand for increased power is there the Howards cam rapidly falls behind.Think about that a second!
when you don,t really need the power the milder cam provides the torque and as long as your not demanding more than part throttle it would suit the demands in most cases rather well, yet if you really want the car to accelerate, its going to fade noticeably , on the other hand the Crower cam provides all the power you can use in the lower rpm ranges AND more power in the UPPER rpm ranges, but it will have a bit less off idle responsiveness.
now everything is rather relative, and if you talk to RICK Im reasonably sure he can describe the way that cam responds to him pushing his foot down on the throttle,and I doubt he will tell you hes found it seriously lacking in responsiveness or power. and so can I, having installed and run it previously in my 1985 TPI 383 powered corvette. every choice you make is a compromise, personally I selected a CRANE 119661 as ideal for my particular combo and I tried at least a dozen cams over 7-9 years .
keep in mind its not just the cam, factors like gear ratios stall speed car weight header design come into play my vettes got the same 3.73 rear gears but it has 25" tall tires and a 700r4 trans with a 3200 stall converter

keep in mind the formula for horse power
torque x rpm /5252=hp
higher rpms allow,and engine matched too proper gearing to have the engine perform more work in a given time frame


BTW
one of the cams I tried after listening to a friend give it rave reviews was the Erson 119824 WITH 1.6:1 ratio roller rockers and a TPI intake, having good off idle torque and good power all the way to the peak rpm where the stock auto transmission shifts at, I must admit but it lacked power above about 5000rpm, ESPECIALLY after I swapped to the ported holley stealth ram intake
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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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