bits of crossfire info



bits of crossfire info

Postby grumpyvette » February 1st, 2009, 5:46 am

posted info from a different site

"Here are some of the more common things I've seen with the CrossFire system.
· Coolant Sensor is faulty - the gauge gives a false sense that it's doing okay, but the sensor that the ECM reads is totally separate from the one the gauge reads! Pinging on acceleration during warmer runs are noticed. If in doubt, just replace the thing. The one the ECM reads is in the FRONT of the manifold - has two wires (black and yellow) going to it.
* Throttle Position Sensor is faulty; can give strange results. Bad idle, great high-RPM power. Always good idea to check this thing out. Uses a +5v reference to send voltage to the ECM. Neat trick: setup the output (center wire) to where it switches to full +5v with the flip of a switch. Makes the ECM think you're at full-throttle when you're not. (Good for acceleration with an automatic transmission, which is all the crossfires ever came with that I know of.)
* MAP sensor - this thing reads in the amount of manifold vacuum and sends out a voltage to the ECM. If it's not getting the correct voltage, you can get pinging real bad on acceleration at any temperature. Pull the wires off. If the idle improves, you have a faulty one. Replace it.
* Bad O-rings or filters on injectors. Turn the key, but don't start the motor. Have the air cleaner assembly off and observe the injectors. If they leak, replace the o-rings and injector filters. If they still leak, replace the injectors!
* Bad O2 sensor. Runs rich sometimes. Won't pass emissions for sure! Is suggested to replace every 30k miles or so. They cost around $25 and are a snap to replace. Not a bad idea to replace if you're going to get under the car in the first place. You can run a wire inside your car and read the voltage with a Digital volt meter to see what your air/fuel ratio is.
* Spark Plugs fouling.. often this is due to bad valve seals. One of my tricks is to uncover the plug electrode by "side gaping" the plugs.
* Knock Sensor.. I think this is my problem right now. The "Computer Codes" book said it causes light pinging during acceleration on light loads."

keep in mind that if you replace the stock tbi (throttle body injection) fuel pump in the tank is designed to work with a fuel pressure regulator and provide about 14 psi of pressure ,but they frequently produce less flow and pressure resulting in an engine that runs lean in the upper rpm ranges. if you replace it with a tpi fuel pump for the later tpi (tuned port injection) system those pumps produce approximately 40psi of fuel pressure but pressure is a measure of the resistance to flow that the fuel pressure regulator provides, you'll want to use an adjustable fuel pressure regulator and set it for about 16 psi if your using the TPI pump
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: bits of crossfire info

Postby grumpyvette » February 1st, 2009, 6:04 am

your stock heads,intake, displacement and compression ratio and cam are killing performance. the cross fire intake is the worst offender as it only flow about 170cfm-190cfm
swapping to a EDELBROCK SY1 or OFFENHAUSER with CUSTOM LID removes that restriction
THE EXTREMELY RESTRICTIVE STOCK INTAKE
ok basics
keep in mind the concept of a chain is only as strong as it WEAKEST LINK
the stock heads flow less than 200cfm, the stock intake flows less than 200cfm and the stock cam is designed to max out at about 5000rpm, so you need to change all three components to get a noticeable improvement.

keep in mind the cars geared , stock to run in the 1200rpm-5000rpm power band.
if you want to keep the basic cross fire intake design the renegade intakes designed as a well designed improved flow intake, the OFFENHAUSER crossram intake can be modified for even better flow rates but its a good deal more work,
youll want heads that maximize the low and mid rpm flow potential so look for heads in the 180-200cc port size that flow at least 245-250 cfm at .500 lift
obviously a roller cam will provide more air flow than a similar duration flat tappet cam, but if you go much above 206 duration on an automatic trans youll want a hight stall converter or above about 212 duration on a cam for a manual trans or a auto trans you need to change rear gears to get the full benefit.



viewtopic.php?f=32&t=2796&p=7243#p7243

max stock spring lift clearance is about .470 lift,either of these cams works, both like 1.6:1 ratio rockers
the milder one is the better choice for a daily driver, the longer duration version gives slightly more peak hp but its also slightly less street traffic friendly
read the links and sub links
http://forum.grumpysperformance.com/viewtopic.php?f=33&t=4918&p=13583#p13583

Image
this is the largest cam ID suggest using in a stock cross fire with auto trans , its good for a 25-30hp gain and works with all stock components and gearing

Image
this is the largest cam ID suggest using in a stock cross fire with manual trans , its good for a 30-35hp gain and works with all stock components but it really works much better with 3.54:1-3.73:1 rear gearing and a larger fuel pump and adjustable f/p regulator

ERSON MAKES TWO SIMILAR CAMS


E110018K
specs>> 270/280 204/214 .420/.443 112 $111.72
buy now
E110020K
specs>> 275/278 209/216 .435/.455 112 $111.72

http://www.pbm-erson.com/store.php?catId=334&parent=333&grandparent=327
http://www.technovelocity.com/chevyhack ... olish.html

stock sy1 intake
Image
custom lid SY1
Image

compare the ports, the SY1 flows about 270cfm
Image
Van Mattiza from Edelbrock indicated the SY1 was made in the late '70s and early '80. The castings were either broken or lost and would not be produced again.

SY-1 Intake Article Nov 2002 Car Craft had a resto article on an SY-1 intake they picked up at a swap meet. While they were playing with it they dropped it on an engine on a dyno. Results: "we found prestigious midrange torque, making 466 lb-ft @ 4600 rpm and 468 hp at 6000 with a Holley 750 compared to 443 lb-ft at 4600 and 486 hp at 6300 with the same carb atop a modern Edelbrock Victor single-plane intake." Article does not say how the small block engine was cammed or what heads, but the SY-1 produced very respectable numbers.


<b>"A MODIFED EDELBROCK SY1 WITH CUSTOM TOP MATCHED TO 190CC AFR HEADS CRANE 114142 CAM -- AND add a 383 high compression engine kit"
Image
Image
Still think you should look into the SY1 Edelbrock intake(pictured above), there is only so far you can go with the CFI intake
b>
BTW Ill save you the math, youll need to get the 10:1 cpr flat top piston 383 kit for the street, and the 74cc combustion chambers AFR 190cc HEADS with L98 spark plug angles if you intend to run high test gas you find everywhere (some is lousy quality) and get the head gasket as close to .018-.022 as you can for correct quench
fyi DD-2000 and EA pro both guess at OVER a 115 hp improvement at the rear wheels, having done this type mod in the past Im reasonably sure thats UNDERESTIMATED for those listed changes

383 rebuild kit $1000
http://www.strokerkits.com/383.htm
crane cam/lifters $150
AFR heads $1200 http://www.flatlanderracing.com/cylhead_index.html
SY1 with custom lid $500-$600
DOING YOUR OWN WORK>>>>>PRICELESS! :thumbs: :thumbs:

MORE USEFUL INFO

http://www.swko.net/~lionsden/crossfire.htm

http://www.swko.net/~lionsden/crossfire1.htm

unless your rich or hopelessly masochistic get a SY1
Image
the sy1 flows close to 270cfm out of the box, a cfi flows 170-190cfm (DEPENDS ON WHICH PORT (STOCK) and there's not enough room to port without cutting/welding (EXPENSIVE AND TIME CONSUMING AND EASILY SCREWED UP)

Image
Image

these are the STOCK CFI INTAKE RUNNERS,

you can extensively port them
and its a big improvement over stock.....if you do so,........but they are still EXTREMELY RESTRICTIVE, and its not a huge help, if your looking to make significant hp


THEY WILL NOT SUPPORT A LARGE INCREASE IN HP WITHOUT MASSIVE CUTTING AND RE WELDING WORK,WHICH COSTS FAR MORE AND WORK FAR LESS EFFECTIVELY THAN AN SY1 SWAP WITH A CUSTOM LID

Image
this is the port work necessary to get them to flow even as pitifully as a TPI

just a bit of info on those stock #624 head flow rates

.......intake....exhaust
.100..44..........41cfm
.200..101..........82cfm
.300.155..........125cfm
.400..182..........137cfm
.500..196..........140cfm


READ THIS ALSO

viewtopic.php?f=44&t=623
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: bits of crossfire info

Postby grumpyvette » February 1st, 2009, 6:06 am

THE OFFY base IS STILL CURRENTLY MADE, and can be adapted

Image

http://store.summitracing.com/partdetail.asp?autofilter=1&part=OFY%2D5893&N=700+115&autoview=sku

Image

http://store.summitracing.com/partdetail.asp?part=OFY-5902

http://store.summitracing.com/partdetail.asp?part=OFY-5903

the basic crossfire manifold is a HUGE restriction EVEN if ported to the max, the XRAM is nothing but a single plane carb intake with a mickey-mouse adapter to allow the TBI injection to be bolted on.

read thru this

http://www.swko.net/~lionsden/crossfire.htm

either the OFFY or the SY1 intake base, with a custom top plate will be a HUGE improvement, easily able to support 500hp or more on a correctly configured engine with decent heads like the AFR 210cc or AFR 195cc

http://www.airflowresearch.com/210sbc_rh.php

and a decent cam like this crower

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00404&x=25&y=17

installed in a 10.5-11.0:1 cpr 383

but keep in mind youll need a 3000rpm stall converter and 3.73:1 rear gear to run those
keep in mind INTAKE HEADS AND CAM and COMPRESSION ALL must be upgraded to get full flow into the heads , so that the power levels your looking for can be achieved,and the stall and rear gear must be changed to use the significantly higher rpm power band effectively, but theres no comparing the results after the mods are correctly made, youll have well over 140 plus MORE hp,(plus) if you do things correctly
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: bits of crossfire info

Postby grumpyvette » February 1st, 2009, 6:07 am

a chain is only as strong as its WEAKEST LINK
and an engine will be restricted to its most restrictive component and the rpm range its filling its cylinders effectively in and burning the charge efficiently in..

just a reminder, stock heads , even ported won,t flow well enough to use the cam or intake potential. and stock,stall converters , 2.571-3.07:1 rear gears will be miserable to drive because you'll spend a huge amount of time out of the effective power band on the low side and won,t be breathing well enough to take full advantage of the upper rpm potential flow without the full package.

an intake that potentially flows 300cfm , matched to stock heads that flow 200cfm , flows 200cfm and runs like a dog! and add a cam that's not opening the valves, or even one that is with restricted heads and you gain little if anything but a loss of low rpm power and no compensating gains with out the heads and gears/STALL to put you into the new higher rpm band where all the powers made


http://www.rbracing-rsr.com/runnertorquecalc.html
http://www.wallaceracing.com/calcafhp.php

http://www.wallaceracing.com/runnertorquecalc.php

http://www.wallaceracing.com/dynamic-cr.php

http://www.chevytalk.org/fusionbb/showtopic.php?tid/131229/


info worth reading, yes you can install the stock or modified TBs on an OFFY INTAKE, with the proper adapters

http://www.digitalcorvettes.com/forums/ ... p?t=101038

http://www.thecubestudio.com/CrossfireT ... ration.htm

http://www.thecubestudio.com/CrossfireT ... shings.htm

http://www.thecubestudio.com/CrossfireT ... Screws.htm

http://www.thecubestudio.com/CrossfireT ... ancing.htm

http://www.thecubestudio.com/CrossfireH ... ometer.htm

Image

http://www.superchevy.com/technical/eng ... _test.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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Posts: 14105
Joined: September 14th, 2008, 1:40 pm
Location: florida

Re: bits of crossfire info

Postby grumpyvette » February 1st, 2009, 6:08 am

grumpyvette?
I was thinking about doing the x-ram since they don't make the sy1 anymore. I dont have much money. just put a side exhaust on it. how much would the 383 cost and how much hp would i put out?


the X-ram is basically a restrictive adapter that allows you to run a less than ideal carb intake on the 1984 vette, under the adapter with the stock tbi injection, mounted on the adapter, its a slight improvement , but a bad design in that its never going to allow the flow numbers and air/fuel distribution necessary to make decent hp

max stock spring lift clearance is about .470 lift,either of these cams works, both like 1.6:1 ratio rockers
the milder one is the better choice for a daily driver, the longer duration version gives slightly more peak hp but its also slightly less street traffic friendly

E110018K
specs>> 270/280 204/214 .420/.443 112 $111.72
buy now
E110020K
specs>> 275/278 209/216 .435/.455 112 $111.72

http://www.pbm-erson.com/store.php?catId=334&parent=333&grandparent=327


heres a whole bunch of crossfire info

http://www.crossfire.homeip.net/

but once you get tired of spending cash and time beating a LONG DEAD HORSE...change the intake, cam and cylinder heads and you'll make progress
guys have spent THOUSANDS of hours and thousands of dollars to get a crossfire running in the 12s,:crazy: if they abandoned the crossfire , and took the same time and cash to build a better design they would easily be in the 11s or faster :thumbsup:


EXAMPLE

http://airflowresearch.com/articles/article085/A-P1.htm

or

http://airflowresearch.com/articles/article031/A-P1.htm

or

http://airflowresearch.com/articles/article032/A-P1.htm


]I was thinking about doing the x-ram since they don't make the sy1 anymore. I dont have much money. just put a side exhaust on it. how much would the 383 cost and how much hp would i put out?

you can usually find USED SY1 intakes on EBAY for under $400

a 383 will generally make about 40hp and 40 ft lbs more than a similar 350 combo with the same parts and at about 300rpm lower in the rpm range.
cost depends on components used, if your working on a strict budget you could probably convert a 350 to 383 displacement , useing mostly your old parts where they will function for about $1000-$1500


the most common 383 combo Ive used that got good results used 10:1 cpr and this cam, and 1.6:1 ratio roller rockers

http://www.cranecams.com/index.php?show=browseParts&action=partSpec&partNumber=114132&lvl=2&prt=5

in a 383 upgrade you can use stock gearing and be fine.
it will work with the stock computer and stock tq converter or the manual transmission.
Ive generally either used the trickflow or AFR heads , but the stock heads will function fine, youll just be down about 45-80hp from where the better heads would be.


heres some sources for parts ID RECOMMEND,

http://www.ohiocrank.com/chevsb_rotate.html

http://www.dougherbert.com/

http://www.adperformance.com/index.php?cPath=277&main_page=index

http://www.summitracing.com/

http://www.jegs.com/

http://shop.enginekits.com/osb/specials.cfm

http://www.lewisracingengines.com/
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: bits of crossfire info

Postby grumpyvette » March 2nd, 2009, 8:22 am

EZELLM posted this info

not getting fuel pressure on your 1982 crossfire this info might help

"<QUOTE>
The electric fuel pump draws high current, so it is not controlled directly by the ECM. Instead, The ECM controls a fuel pump relay which in turn controls system voltage to the fuel pump circuit.

When the ignition is turned ON, before the starter is engaged, the ECM turns on the fuel pump relay for 2 seconds by providing ground. If the ECm does not receive ignition reference pulses from the ignition module within the 2 seconds, it shuts off the fuel pump relay until the engine is cranked. The ECM grounds the relay circuit as long as it receives ignition reference pulses. <UNQUOTE>

Because the schematics in the books I have are really bad, I'm going to list the wiring in this circuit from a separate. . . . .

ECM:
ORN 340 - pins B1 and C16 receive power from the battery junction block through the fuse holder, and is also shared (common) to the oil pressure switch, and pin "E" (normally open) contacts of the fuel pump control relay.

DK GRN/WHT 465 - pin A1 provides the 2 second, 12 VDC to pin "C", the positive side of the relay coil.

BLK/WHT 450 - pin A12 provides ground to pin "B", the negative side of the relay coil.

TAN/WHT 120 - pin B2 provides voltage monitoring for the fuel pump motor - this wire is tied to the positive side of the fuel pump, pin "A"(normally closed) contact of the relay, and the other side(from that mentioned above) of the oil pressure switch, and pin "D"(closed) contact of the relay.

>>Just know that power is from the fuse panel through EITHER the pump relay OR the oil pressure switch, as they are in parallel with each other. the oil pressure switch is parallel to pins "E" and "D" of the relay. THAT'S what allows you to bypass the relay by jumping the oil pressure switch.<<

this might help also

viewtopic.php?f=32&t=596

http://www.autozone.com/shopping/repair ... 528008fdea
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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Posts: 14105
Joined: September 14th, 2008, 1:40 pm
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Re: bits of crossfire info

Postby grumpyvette » August 11th, 2009, 4:55 pm

http://5finger.8m.com/tpi2carb/tpi2carb.html

viewtopic.php?f=55&t=635&p=3150&hilit=+regulator#p3150

read this as a start, if your thinking of swapping to a carb set up to avoid the CROSSFIRE hassles
there ARE combo deals

http://www.summitracing.com/parts/CMB-03-0193/

http://www.summitracing.com/parts/CMB-03-0147/

just a bit of info on those stock #624 head flow rates, are below and the stock cross fire intake made even those flow numbers difficult to maintain

.......intake....exhaust
.100..44..........41cfm
.200..101..........82cfm
.300.155..........125cfm
.400..182..........137cfm
.500..196..........140cfm



Image
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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Site Admin
Site Admin
 
Posts: 14105
Joined: September 14th, 2008, 1:40 pm
Location: florida


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