Hi my friend and I are swapping a 305 motor from a 87 Firebird 5 speed into a 86 Iroc with a 305 auto due to lower engine knock. I know the cylinder heads, distributor and cam are different but my question is will I have any problems with the car running properly or what not with a different year computer and putting the 86 distributor in the 87 motor.

Thanks a lot
Joe

The diffrence between the 86 and 87 motor is all in the cam... I really doubt the distrobutors are any diffrent. The ECM might be diffrent along with the wireing harness (I know the 87 uses a knock sensor I do not know if the 86 does) but everyhting will bolt up and work.

Actually I'm pretty sure they changed more than that in 1987. As I understand it the ECM may be different. Also they switched head styles from 3 bolt to centerbolt. The cam is different. Also the knock sensor should be the same.

That's why you see alot of stuff that says 1985-86 and 1987 and up. When your looking for parts for the stock engines.

87+ are hydraulic roller engines.
I'd swap out the ecm as well.