Cutouts for Strip only, beneficial?

A 512 in a Scamp? That ought to EASILY run what you're after! I suspect you are traction limited? I'll bet that big motor makes a ton of torque and the car needs some help with traction. The cam is small for that big of a motor so the top end power is likely lower than it's capable of. But my goodness, with that much displacement, I see no reason you can't run what you want without cutouts.