what heads would make the best horsepower for a 355 15pd procharger lt1 engine. I have a 94 camaro. next summer I'm having a 355 built up with a 15 procharger. I wanted to know what heads I should go with or just have the stock ported?? What about afr???canifeld???

 

Generally you want the largest ports and valves you can get without sacrificing drivability in a FI setup. The inertial effects aren't near as important in FI as is it is in a NA car since everying is under pressure in your intake track, vs. NA where everything is in vacuum. The larger the ports and valves, the less resistance you make for the air being forced in.

Thats why you can take an engine with a 15psi supercharger and port the heads, and when you put them back on you'll be making less boost but more power. Plus less restriction means less heating of the incoming charge. You have more air entering the CC that's cooler, so you make more power.

Look at INTMD8's car... 355 with ~215cc intake ports (more efficient AFR ports) and 20psi of intercooled boost. About every LT1 i've seen that had ported stock heads(~200cc) running that much boost didn't make near 850rwhp.

 

I'm building a 357 CI LT1 for Forced Induction and I am starting with bare AFR 210CC LT4's that I recently purchased. I have heard that once they are fully ported, they are about 215 to 220 CC intake.

 

why did you decide on a 357 over, say, a 355?

 

Because I got a really good deal on a new Cola 3.50 inch forged crank that I could not pass up. I did not want to go the stroker route because I didn't want to spend the extra money on the clearancing of the block, etc. I would rather put that money into the heads and elsewhere.