RFP for the Engine Build for the Missile

As mentioned - excellent heads, wrong intake, wrong cam (by a long shot). If you want 600hp, you have to get the air in and out. Look at the jump in DJV's 430 with the right heads and camshaft. And you have a much better (IMO) set of heads. With a mild solid roller you could sail past 600hp and be really nice at any rpm you wanted.