420 HP Edelbrock RPM setup for smallblock chevy. 9.5:1 Pistons, Edelbrock RPM Series aluminum heads, Edelbrock RPM Airgap manifold, Edelbrock's cam and lifter kit, & a AVS Thunder series 650 CFM Carb. That produces 420 HP for about, i dunno ... around $3,000, if the parts in your smallblock are built to handle horsepower in that range, just hook some nitrous up to it to get 500 hp. You could buy a big block, but it wouldnt be as cool lol.