[Longhorn 70]

The LT4 in the Vette in my signature does over 375 at 6150 RPM to the ground on a chassis dino. That calculates out to 450 at the flywheel if you allow 16-17% drivetrain loss.

It has 383 forged bottom with cleaned up LT4 heads, a bit higher lift than the LT4 HotCam, PM HBeam Rods, roller rockers and lifters, extrude honed intake with injectors and computer tuning. It is a bit lumpy on the bottom end but with balancing you really don't feel it.

As this is a 6 speed, what the OP said he was going to use, it does make it more comfortable on the street. Lingenfelter and others build harder running small blocks than I have that work well on the street.

The Muth'a Thump'a cams or similar with E-Force heads are a great start for the top. Forged stroked bottom with proper block prep and assembly will get you close.