The Ritter block with the P5 head at 434" and two carbs would do it pretty easily I would think. Even at 410" should be no problem. Call Patterson up and talk to him. He told me to find a set of heads and he would build me one for a turbo application. The P7 would be my second choice.

2010 Toxic Orange Challenger built by B and B Racecars! All aluminum R4/P5 engine, Proformance TH400 (3 speed) tranny, full Reid case, nodular 9" rearend, full Dragpak suspension, Protorque custom converter, BS3, PTE 85mm turbo, fire core wires, carbon doors, carbon front clip, and a whole lot more!