Girlfriends 84 Corvette has a 350 Crossfire Injection engine and wants to buy my TPI system off my 86 IROC Camaro. I'm pretty sure everything will match up, my only concern was the 4+3 Transmission. Will we have to find a new ECM since hers is a stick and mines an auto?

Any other info is appreciated also.

 

I think that it would basically be the same process as switching from an auto trans to a 5-speed in an F-Body. Would need a chip designed for a 1986 manual trans TPI car, as opposed to an automatic so it's not looking for a lockup torque converter to be plugged into it, etc.

Obviously you'd want to use your F-Body TPI wiring harness and computer since the CFI Vette stuff is significantly different. I also think the Vette used a weather-tight ECM under the hood where the FBody ECM was

I am unsure what differences there would be between the 4+3 and an FBody 5-speed with respect to computer hook-ups.

Also, your 86 is a 305 TPI engine and the Vette has a 350. The calibration will be different between the two as far as running the engine goes. Different fuel maps, etc. My expereince is that MAF-style TPI setups like on your 86 are more forgiving of increases in displacement and other changes than later speed/density systems but don't expect anything like perfection with the stock 305 programming.

 

Yes but i got an ECM out of an 87 IROC with a 350 because i'm running a 383 now, so the calibration should be about the same. We planned on getting a chip burned anyway just to match it up even more.

 

I have a 4+3 in my vette the trans. I want to upgrade to a 6 speed richmond when I can find one used. The 4+3 three is really a 4 + 1. With a highend motor you can burn the overdrive out in a minute. Only engage the overdrive over 40mph, then you can nail it. Evey one gets all worked up about the computer. It is all BS. Put a switch on the shifter. ON and OFF and you are done.
The trans works ok but it is nicer to shift all five gears hard. Not four then an automatic engagement. See http://www.5speeds.com they have all the parts and the problems identified with this pile of junk


Frank