What is the PROM ID supposed to be for my 91 z28 that has a tpi 305? The current ID is 5291. I'm just trying to make sure that I don't have a 350 PROM in the motor.

 

the prom code is AWFW 5514. Would someone be able to tell me if that is the correct prom for a 5 speed 305 tpi?

 

Go to your frindly Chevy dealer and see what their parts manual shows for your car. They call it the 'memcal'.

 

I tried that. My 'friendly' chevy dealer has the mem-cals discontinued and they advised me on going to Auto Zone Lol. Which I had done before heading to the damn dealer. The only thing I can think of is getting the one from Advance which is a stage one performance chip that costs 250

 

What makes you think that you have the wrong Prom in the ECU??? If the 305 is Stock?? it would not have the 350 Prom and even if it did, it still would run with no problems.
Also forget about those Auto Part store Proms, a waste of money for what they do. If you really need a new Prom I would suggest Fastchip.com, Ed Wright has the best off the shelf Proms that work. Have one in my car since I swapped in the 350 eight years ago.

 

I thought it had a 350 prom in it because I was reading someones replay to a post about their car 'bucking', or being really jerky when just accelerating regularly, which is what my car does. It runs fine when getting on it, but just doing a casual acceleration it just doesn't run right. One guy replied saying that it might have a 350 prom in it because they have different spark advance curves and stuff like that. It just sounded like what was wrong with my car. But taking the prom out, getting the number off of it, which happens to be an AWFW 5514, I believe, it is the correct prom. So now I'm back to square one.

 

Black, if it has a 350 prom it will not run right. It will have timing off and run a bit richer.

I had this happen in my iroc. We thought it was bad gas because it would accelerate jerkily between 1-2k rpms.... Turns out the idiot I bought it from threw a comp from a 350 without vats in to bypass the vats and never test drove it just started it up.

Got the original comp, threw it in, bypassed vats.. problem solved.

 

ECU for a 305 & 350 are the same the Proms are different. 350 prom (chip) will run a 305 but not as well as was intended..