I am currently the owner of a 1989 Camaro RS 5.0 5spd. I want to convert the car to a 350 TPI or build a 305 TPI. I baught the TPI unit with all strings attached with ECU and wiring harness for really cheap with a 305 motor. Just curious but does anyone have any instructions as to how I should go about changing out the TBI to the TPI motor? Is there anything special that I have to do or just rip the computer from the old motor out and put the new one in? Would it be more worth while to keep the motor with the TPI or can I put the TPI and heads on a 350? And if I did that would it work out with any block or only L98 blocks and newer? I would be very grateful if someone could walk me through the procedure of putting the TPI 305 in because I would much rather build a motor with a matched intake than trying to mix and match it. Any ideas on the build up would be nice too.

 

Personally, I'd swap the TPI onto the current engine just to make for easier troubleshooting.

There is an article in the Tech Articles section that covers the high-level process, you'll want wiring diagrams for both your car and the one the TPI harness came from...they typically aren't plug 'n play.

I did a TPI swap into my '82 Z28, spent about 2 days repinning the '88 GTA wiring harness to work with the '82 chassis harness.

 

"I would much rather build a motor with a matched intake than trying to mix and match it. Any ideas on the build up would be nice too"

Sounds like you are off to a good start with that Idea in mind!
If you are going to convert to a 350, I would start your buildup going from there. To answer some of your questions, YES the 305 TPI heads can be used on a 350 with nice results,(on an early or later model block). Most people would recommend porting them a bit before putting them on. There are things that sometimes have to be changed to make eveything compatible when going to an older style block, but nothing that you cant find help with on these boards. Do you have a specific 350 block available? What year heads and TPI do you have? Also, try doing a search on these subjects. There is most likely all the info already posted on these boards with these very same subjects that can walk you through almost everything.