1982 ECM & Compression
#1
Advanced
Thread Starter
1982 ECM & Compression
As i narrow down the best performance cam and heads for my 82, doing my research on this forum and other sites. I thought i saw somewhere, but now can't seem to find it again that a compression over 10:1 would cause problems with the ECM. Is there any truth to this or did i imagine it? If it is true, would an aftermarket ECM help in any way. I know my choices are limited for this year and have read mixed results with the performance ECMs.
Appreciate the help!
Appreciate the help!
#2
If you changing the cam and heads already why arent you installing a non-ecm distributor and switching to a carburetor?
#3
Advanced
Thread Starter
Thanks!
#4
Melting Slicks
Here's my recipe for a hotter 82:
Summit (dart) heads #152123 -- 72CC, 165 runners
Renegade intake
Lunati Voodoo cam 60100
Hypertech chip
1985 fuel pump (ep241)
delete cat
HEI perf tune
your L83 is already a 9:1 motor so you cant go much higher with iron heads on pump gas
Summit (dart) heads #152123 -- 72CC, 165 runners
Renegade intake
Lunati Voodoo cam 60100
Hypertech chip
1985 fuel pump (ep241)
delete cat
HEI perf tune
your L83 is already a 9:1 motor so you cant go much higher with iron heads on pump gas
Last edited by Fast81; 08-16-2018 at 04:06 PM. Reason: more info
#5
Le Mans Master
I like that you are trying to stay with the crossfire.get all you can out of it .then tell us how far you got with the factory set up .Then I would get what ever manifold you like and put a fast fuel injection on it. what hp are you hoping for?
#6
Advanced
Thread Starter
HP would just be a guess, if I can get into the mid 13s then I would be happy. For a street ride that’s not bad. I’m ready to order the parts if I can get a question to this compression and ECM question. Right now I’m right at 10:1 with the changes I will be making.
#7
Race Director
Aren't you replacing 72 cc heads with 72 cc heads? Where is the extra compression coming from? Oh, somebody else, not OP with the Summit heads.
Last edited by derekderek; 08-17-2018 at 10:53 AM.
#8
Melting Slicks
82 OEM 426624 heads are 76cc chambers (1960s design) with 158 cc intake ports
Summit (dart) heads are 72cc chambers (modern 'heart' design) with 165cc intake ports
Summit (dart) heads are 72cc chambers (modern 'heart' design) with 165cc intake ports
Last edited by Fast81; 08-17-2018 at 11:55 AM.
#9
Advanced
Thread Starter
Currently looking at 64cc heads with .03 gasket which will put me around 10:1. Trying to get good compression without wigging out the ECM but I can’t seem to find out if it will be a problem. Have not ordered any parts yet
#11
I started with a mild cam, 64cc heads (I used RHS 200 runners with 64 cambers with .041 Felpro gasket), Stainless mid size headers, ported stock intake and Hypertech chip. I also rebuilt the throttle bodies. Really wakes up the stock motor and it still will cruse anywhere you care to go.
#12
Team Owner
There is no reason to dump the ECM and other engine control stuff just because someone else can't deal with them! As long as the stuff you put on that engine can produce the proper fuel/air ratio for the engine (as read by the O2 sensor), the ECM system should work just fine. If you want to build a 500+ hp screamer with 12:1 compression and which needs AV gas to run, maybe you want to start with something other than a CrossFire engine. If the ECM and components are in working order, you can change heads/cam/pistons/exhaust/induction system and it will work just fine.