E58 400 plus HP Dart sport build

See engine labs dyno build 360, I do plan to do some head work and I'm bumping compression up as well 10.2 to 1 should be right on the edge of 400 with better compression which they left bottom end stock pistons. Modifying And Testing A Dodge 360-Cube LA Small-Block On The Dyno

It's going to take more than "mild" porting (bowls and window clean up) and not moving more material. I never believe anything off that particular dyno until it proves it at the track.