i recently replaced a 305 for a 383 in a 91 rs. i used the 305 heads, intake, distributer, and 350 injectors, it has a .495 lift cam. i had a custom chip made, but i am still having some issues. the car idles good til in gear, and it has a dead spot when acceleratoring til it warms up, the plugs are carbon fouled. any suggestions?

Sounds like a bad tune to me. Fouled plugs means it's pig rich. A dead spot can also be a result of parts of some of the cells in various tables being way off. My corvette did that... At certain conditions the car would stumble, and my scan tool revealed a momentary lean condition. Cranking the fuel pressure eliminated that issue, but obviously caused other problems.

thanks for the response, ive ordered an aldl cable and program to connect with my laptop, hopefully i can see the problem. if i up the fuel pressure to take care of the dead spot, i will still be running to rich, right. what do i do about that? thanks

I assume you still have TBI on the engine, so if that's the case, I'll move this to that forum where you're more likely to get useful information.

ok sounds good to me, thanks

just let me know which one it is, thanks

your running a 383 with stock 305 heads??? rip those damn heads off and get some decent heads on it. your suffocating the engine lol

would a set of stock 350 heads be better? im on a tight budget