I have a bone stock 86 iroc-z with a total ground up rebuilt of the engine every part has been checked over and measured to correct specs, i was wondering if anyone can give me ideas on what to modify the 305 TPI rebuilt engine that i have, like heads, cam, exhaust, chip, and ec...... Oh it has a 700r4 tranny but that hasn't been touched, Im looking for a tweeked 700r4 if anyone has or knows someone that is selling a tweeked 700r4 please let me know, also i would like my Iroc-z to at least have in the ball park of 300-350 horses!!! let me know thanks!!

 

One of the big power-limiting issues you'll confront is the TPI itself. The runners are too long and small for higher RPMs (where the power is made), and since the induction is "tuned", your powerband is a little limited. But, with shorter/larger runners, ported base & plenum, you can improve power substantially.

The cam & heads are the next restrictions, the CompuCams are pretty nice (mine is probably a little too big for TPI, though - perhaps a 2030 or 2040), and the World S/R Torquer 305 heads are arguably the best 305 heads out there after they've been cleaned up per Standard Abrasives DIY guidelines.

Headers are the next logical step. I believe you should have 3" cat already, if not, do that and 3" cat-back as well.

Chips - check with the TPI board guys and DIY PROM forum. They'll have the info you need.

Unless you get pretty wild with the TPI (BigMouth, big cam, etc.), it's pretty hard to top 300 hp with a 305. Possible, just more expensive. You can do it a lot better than it was, though, with the above.