[dkjos]

Just speculating, but 1 HP per cubic inch should not be too hard to get, based on the 351W Don Scott built for me. It has a Comp Cams Extreme Energy Cam, GT40P heads, 9.5 to 1 compression ratio, Edelbrock Performer manifold and a 600 CFM Edelbrock carb. Relatively low cost(heads are only about $550 per pair assembled) and it put out 351 HP on the dyno with loads of torque(390 FT/LB minimum from 2500 to 4400 RPM).