I recently swapped my 305 for a 350 crate engine and kept the TPI system. It's common knowledge that no 350 chip is compatible with the stock 85 ECM. Is it possible to wire in an ECM from an 85 Corvette? What are, if any, the differences between the TPI in the 85 Corvette and the TPI in the 85 IROC-Z?

 

I just aquired an ECM off Ebay via "buy it now" feature. The ECM number is 16198259. No chip is included. Now I don't know which chip I should buy. Any suggestions? The item description said "TPI GM 1986-89 MAF ECM 350 305 COMPUTER". Will any chip from 1986-1989 (with 350) work with this ECM?

 

I have a question. Why besides the timing tables wouldn't a Prom from a 1985 TPI Vette which runs a 870' ECM work.

Have you checked in to burning your own chips and then you can do any thing You want.

Even on the fly Tuning with the AutoProm and Prominator. Checkout the DIY Prom

 

Can use any number of chips (MEMCAL) in that ECM. The ECM number posted is the newer number for the 1227165 ECM. If you get a '89 MY MEMCAL the cold start injector will need to be disconnected. An '89 also has VATS, so it may not be a good bet.

If you don't burn your own EPROMs then I would also stick with an f-body MEMCAL. The Vette MEMCALS have some items that are different such as fan relay polarity, VATS, oil temperature. . .

Not sure if you know but on Davis's site he lists the changes required to upgrade the ECM from the '85 ECM to the newer '165 ECM.

RBob.