Does anyone happen to know if the '89 iroc and '91 rs camaro ECMs are comaptable enough to do an engine swap? I know that several aesthetic changes were made in 1990 as well as the switch from MAF to speed density. However I have heard rumors that the vss that drives the speedometer is different as well and may be driven by the ECM? Is this true or will my 91 guages work using the 89 ECM? Or are there other pitfalls I am overlooking?

 

if you use the 91 pcm youll have to delete the maf, check out thirdgen.org i know a few guys who swithed to the speed density pcms and use burners to burn chips for tuning. your speedo should work, i know a guy in prince george using a 92 pcm on his 88. but to be sure check out http://www.thirdgen.org/techbb2/