383 rebuild - kinda whimpy on the dyno?
Years ago I seen some development work in an article by Dan Dvorak Port with some iron heads. Port work that would take full advantage of the flow of the larger valve sizes in a 906 head would turn a 383 or 400 into a whole different animal, indeed. Something that would take a minimum of 11:1 and a stout solid cam before reaching the limits of port flow. It would probably have a torque curve/rise rate more like a 340 than a big block