I know there are a lot of swap threads but, i haven't found a straight answer. I have a '87 IROC with a 305 LB9 but it has a rod knock so i need a new motor. I want to put a 350 in there but what do i need to replace? Do i need to reprogram my computer? If possible i would prefer a 350 vortec but i'm not sure how much work that will be and if its worth it.

 

anyone? well i was talking with howell auto and they said that for the computer i need to get a prom for a 350?

 

You'll need to burn the prom for the 350 settings or just get the 350 computer altogether, the block obviously, and you'll need larger injectors. I think thats about it.

 

'87 is MAF, which is pretty forgiving to displacement changes. You can always expect to get better performance out of the car with PROM tuning, but it isn't a must-have.

Knock sensor and module should be changed to 350 parts.

Injectors are optional. 22 lb 350 injectors give you WOT margin, but 19 lb will usually do the job.

 

what is the better of the low cost GM crate engines?