I didn't think that the 500 hp we saw from the 432 motor with 906 heads was out of line. Stevie D's "Air Hammer" 440 was pretty consistently in the 630 hp range with his ported iron heads on it. That was just a 0.060 over 440 with a Weiand intake, 12.6 compression, solid roller cam motor.

He had ported 915 heads rather than 906 heads but that shouldn't be that big of a deal. I think he topped that motor out at 660 hp with a tunnel ram but with a single 4bbl he usually was in the 620-640 hp range.