Making power out of the 318

1st thing I'd is drop hp expectations, there's a big difference between a 425 and 500 hp even a 375 and 400 hp depending on heads. Heads basically decides power potential and cam cr etc. decides how much of that potential your gonna use.

Stock 360 heads with reasonable street cam for a 318 with 3.21 probably be in the 325-350 hp with some head work maybe 375 + hp. With a non reasonable cam you could make more obviously. To me reasonable would be under 220 degrees @ 0.050".

So first question are heads gonna be basically stock, minor ported or bigger valves and minor porting etc..

This is basically gonna decide how much hp your gonna make cause cam wise your hands are fairly tied mainly because of rear gears cause you seem willing to add any stall and cr. Could always get a trans with lower 1st and 2nd gears and get away with a little more cam.