I know this has been asked before butI can't seem to find it in the threads. I am looking at getting a 1987 350 out of a camaro and put it in my 1990 305 trans am. I know what I new to swap to do the 305 to 350 but I wad told there is some difference in some module (esc I think) which differs between the 80's and 90's motors. Just want to know what this is and would it be a problem. Also are the intake manifolds the same on both motors? I know the intake is but not sure about the manifold if I could just use the whole 305 stuff and not have to worry about this module problem. Thanks.

 

You just swap the 350 in underneath all the 305 stuff you have , ECM , wiring etc.
Need a 350 prom ,350 knock sensor and 350 injectors

 

Ok so what is the difference that I would normally have to worry about between the 80's and 90's motors?

And is the intake manifold the same between the two motors?

 

What he's saying is not use any of the '87 stuff except the engine itself - remove all of the intake, etc., from the 350, put the 305 intake and stuff on. The '87 intake is different from the '90 intake, but the '90 intake will bolt right onto the '87 engine.

The '87 injectors will work in the '90 manifold, so that part is okay. You will need a '90-'92 350 PROM for the '90 computer (or get your 305 PROM reprogrammed). I think the '87 350 knock sensor will work, but I'm not completely sure about that.

 

for the swap you are doing , not 80's vs 90's but MAF vs MAP fuel control systems. Your 90 is MAP ; the 87 is MAP.

You can modify the 87 MAF intake to work on a MAP engine but seeing you already have a MAP intake on your 305 why go to the trouble ?
As noted , swap the intake over and all your existing 305 wiring goes back in place on the new 350

 

Alright great thanks for the help!

 

Just to be clear, should be: "Your 90 is MAP; the 87 is MAF."

(Just a typo, I know)