for 500" a PORTED Street Dominator. Worth at least .10-.15 over an unported one.

The Indy 440-2D is another good choice, but the lower plenum needs some radius work in the runners to get it to flow with the upper. The Performer RPM is a great manifold, but too tall unless you run a drop base air cleaner.

The MP 337 is listed as a Max Wedge but the head mating port size as delivered is really about 1/2 way between a standard 906 size port and a true Max Wedge...probably could make it work and it's a nice flowing manifold.