Any of you guys done the TBI to TPI swap?
Anybody got pics or know if there is a manual or at least a good resource to help with the swap? I just bought a TPI system off an 89 Iroc 305, I got ECM, wiring harness, fuel lines, fuel sender, manifold, runners, plenum, TB, various nuts and bolts. The guy i got it from at the junk yard said if I needed anything else off the car i could get it.
My question is what do i take off my 89 RS when i take off the TBI, and how do i tell which wires go where? Also, what sensors do i need, besides an MAF (it was missing off the donor car)? How hard would it be to convert to SD? What other parts do i need?
Any help will be GREATLY APPRECIATED!!!

Thanks.

 

I contemplated doing the same thing for my engine, but after doing a search, I found out that it won't help much because of the weak cam in the stock TBI engine. I don't think that anyone on this board has ever gone through with it, and the subject comes up quite often.

I think you will also have to add a different computer chip and fuel pressure regulator.

Post this question on the TBI board and I believe that the vast majority will say it's not worth it to just change the fuel injector system without also replacint the cam and rocker arms with better ones.

 

Do you have fuel injectors? Cold start valve? TPS? Are there any holes without something filling them? If you go to the tbi or tpi board there will definately be many people to help you.

Speed density is pretty expensive to convert to I think... MAF is decent if you don't mind cleaning things a lot.

 

Well if you got the prom with the ecm you should be set. You'll just swap manifolds basically, and I believe you'll be able to reuse your distributor (don't quote me). The biggest headache will be the fuel pump. Go back to that junkyard and get the fuel tank or buy a new one for TPI. You have to put in a 60+ psi pump for tpi whereas tbi is only about 15psi. The tank is by far the biggest pita, followed by the fuel lines. Check out Chuck Everly's (et al) article on how to convert to sd tpi, even though you have maf everything is nearly identical. Take out your ecm and get the wire packs out from the fender area, then install the new wires (w/o unhooking anything!!) and ecm and see what connections are all identical. There will be many identical connectors. You'll need a maf, and possibly a different knock sensor but i'm not sure on that one. chances are you'll need help routing vacuum lines but post again when you come to that bridge. good luck.