i have a tpi system from an 86 t/a but i have an ecm from an 89, can i use the 89 ecm with the 86 system? i've been told that '86 used a cold start injector but '89 didn't. what's the difference and what problems am i going to run into?

 

i believe you can. im pretty sure the 86-89 ecms are interchangeable. you are correct about the cold start injector but that is in the prom not the computer. you should be alright as long as you change the chip. the chip you have to use is 86-88.

 

You can do that, or simply keep the 89' prom, and toss you're cold start injector entirely (it'll help to unclutter the engine bay)...

 

what will i do to block off the hole from the cold start injector?

 

you could use a blockoff plate to keep it clean
or just leave injecter there
id go for the blockoff plate and keap the cleaner look

 

You cant use the stock '89 PROM, as it has VATS and the '86 does not
The computer is the same, just the prom is different as Green89IROC said.

 

the tpi system is from an 86 ta but it's going into an 89 formula which also has vats, so will it work? or will i have to change something?
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where can i get a blockoff plate for both the intake and the fuelrail?

 

Then I misunderstood the original post, as I thought he was trying to mate an 86' TPI system (intake, plenum, runners, throttle body...), with an 89' ECM and harness.

That's what I originally thought. Yes, it'll work just fine. Just get yourself a cold start injector "removal" kit, try Summit Racing

Edit: Whoa, wait a second, just glanced at you're sig. Are you trying to mate an 86' TPI unit with an 89' TBI ECM? Or do you have either an 86' or 89' TPI ECM? Lay everything down on the table for us, whaddya got?

 

i have a 1989 formula with the tbi 305, i bought a tpi setup off an '86 T/A in a jy but minus the computer and i now have a tpi ecm from an '89 tpi system. so i am putting together an '86 tpi system(wiring harness intake runners and all minus the ecm) with an '89 tpi ecm to replace my tbi setup
i hope there's no more confusion anymore lol

 

The factory TBI wiring will need to be modified though, and you're going to need additional components (sensors for MAF, TPI fuel pump etc.). Also, you're heads. The 86' intake will need to be drilled so it can bolt down properly to you're 89' centerbolt heads. Unless, you already have these things taken care of already....?

 

Here's an older website for reference;

TBI to TPI

 

i'm planning on getting a set of tpi heads, i have the maf and the complete wiring harness