I currently have a 89 Camaro RS with a 305 tbi. I recently bought a 1988 350 tpi motor with the harness and the computer. It looks like I have everythign I need except for a new fuel pump. How difficult will it be to swap it over and do you have any advise on the best way to do it? I usually swap out carb motors but I wanted to try this swap to broaden my horizon. The expense has been minimal as I picked up everything for $400. The motor has only 78,000 original miles on it so I wasn't even going to rebuild it yet.

 

Welcome aboard thirdgen.org.

The fuel pump replacement basically involves dropping the tank, which requires getting some exhaust and rear end stuff out of the way. Not difficult, just involved.

Changing the TPI system isn't too big of a deal, either. The ECM is under the dash on the passenger side, the harness goes to the kick-panel pass-through into the fender area. Disconnect the harness from the ECM, pull the clip off of the bulkhead connector, pull the harness out of the fender into the engine compartment. Reverse for putting the TPI stuff in. If you have an automatic, one connector goes down to the transmission, otherwise it's all in the engine compartment.

The big gotcha is the exhaust - TBI stuff is small and will choke a 350 (doesn't do a 305 any favors, either). You really need to change all that out as well. If your engine came with the exhaust manifolds, that's one improvement, but the y-pipe, cat, and cat-back all need to go, too.

 

How is the stock exhaust manifolds an improvement? Do you mean between the 305 , or headers? I will also be replacing all the exhaust with 3 inch and probably will delete the cat. How does the tpi respond to all the emissions off? It is a MAF motor as well. I thought about taking the tubes off the manifolds or just replacing them with headers. Not sure of my route with the car as of yet, drag or street.

 

If you put on headers and exhaust for '86-'90 TPI single cat on, the manifolds don't matter. But, TPI manifolds were bigger than TBI manifolds, ditto all the way back.

MAF won't care about the lack of a cat. A.I.R. might be a different matter (sticky about it on the Exhaust forum), but most likely won't be a big deal. No EGR will set an SES trouble code, unless you program it out of the PROM.