You're not going to be able to hit the 500 mark, or for that matter the 400 mark N/A on a 4.6 and keep it as a diecent DD. A nice set of cams, and a blower will get you there, but for reliability you're going to have to get a built bottom end, and a set of Pi heads woulden't hurt either. And on top of that a nice blower.

 

doesnt holley make an intake that has a super charger, i kno its flat and the rod stick out with pully. that might shorten the intake up and give you Boost ?!?!?!