I was wondering if an 87-95 350 tbi truck ecm will plug into our cars, not the prom but the whole computer.The reason I ask is becuase I have seen alot of people having problems when they put bigger than stock cams and heads in our cars with the computer and they end up having to burn custom chips for their cars.Well this weekend I helped my friend put a GMPP 350 HO in his 92 chevy truck and we just hooked it up and fired it up and it ran like a champ. I helped another one of my friends with a 90 firebird do the same swap and he used a cop car chip ,and knock sensor and esc and hes been having eratic idle , and loss of power. Well to some this story up , I am about to build a new engine for my car simular to the GMPP 350 HO so I would rather just swap ECM's than burn a chip, I dont really have the equipment or patience.I appreciate any help I can get on this subject.Thanks.

 

You will need a different prom. The prom tells the car how to run not the ECM. Even if you wnted to switch ECM's I do not think they are compatible. You may want to start with a cop car chip or 350 TBI chip and use the same parameters as a starting point for your new motor. A custom prom is the only way to get all the power you want out of your new motor. The prom in your friends truck will be far more forgiving and "run like a champ" than the one in a stock LO3. 350 to a 350 (with a little more power) as compaired to a weak 305 going to 350 with twice as much power and more cubes.

 

I probably should have mentioned I already have a cop car chip in my car, I dont have it listed in my sig, I did alot of work to get my car running properly after I did the 350 swap , It was well worth it ,and now I am building am building a motor that I want to pull low 13's with,and if I can do it with out burning a chip i am willing to do almost anything to avoid it. my friend was running almost exactly what I am before he put in the 350 HO, and now his runs like crap and i run circles around him with my car which shouldnt happen, the reason I asked if I could switch ECMs is because I was told the truck prom wont work with our ECMs. Thanks for replying.

 

Yes, the 87-92 truck ECM (1227747) will plug right into a TBI f-body and run. I've done two this way.

You can not swap proms from different model ECM's.

Don't know about the 93-95's but I suspect they won't because they are wired for electronic transmissions. I'm not saying its impossible but surely more work.

Prom tuning is the only way to get things optimal. Sure you can use a Vac reference regulator to boost fuel delivery at WOT and have decent results but you will leaving some performance on the table.

How fussy are you about having things optimized is the real question.

 

will plug right in? is the wiring harness in car a direct plug into the 7747 board ? mine was not but i have a 84 vette, not an Fbody..

 

Your's was not a direct plug in because the cfi's did not use the 8746 ecm like the '89-'92 f-bodies.