[klayfish]

Rob,
Simple solution. Get a 514 specifically designed for the driving style you want. I have no doubt that you can find a motor with that many cubes that's a stump puller. The car is going to be a street car just for fun. How often will you really run 5000+ rpm for more than a second or two? For your needs, you should be easily able to design a motor to smoke the hides at the hit of the throttle but still be streetable. If you call an engine builder and tell them your needs, they can select a cam, etc... to fit you. And I'll bet that as long as you don't go nuts and ask for an aluminum engine that can rev to 9000rpm yet still be streetable, you'll probably save some $$$, as big displacement, high torque engines seem fairly common.

Steve