IMHO your best bet for the most hp on the cheap is offset the stock crank to 3.90 for 470 cubes. You said you didn't want to stroke it, but that is a great combo for a stock size port head! The extra stroke will help with a heavy car is a street strip type of setup because the motor will spend a lot of time in the lower rpms of the first half of each gear. Paint the right set of aluminum heads for the look, get good quench of .040 with a reverse dome piston, 7.10 H beams to help with lightening the rotating assembly. ANDYF really liked the Mopar 528 mechanical cam with stock manifolds, so something real close if not that cam. Research where the best gains are on reworking those stock exhaust manifolds. No experience with them here, but I am thinking it might be possible to get some gains by opening up the outlet area and using the right sized pipe for the full exhaus5 system, plus the right CFM flowing mufflers, cross over, etc to keep every Hp you build into the motor.