Its whats under the bonnet that counts!
Sport Compact should allow anything non-V8 to run, regardless of what originally came in the body style. To prevent V8 bodies simply limits competitors and increases cost. A case in point is Aaron Gregory who has spent all his readies to build his 2J powered Pontiac, and now has to sit on the side line until he can get the cash together to buy a body shell that never came with a V8. The chassis would be the same, the aerodynamics possibly better (ie faster), the motor unchanged but he would then be allowed to race. That situation is ridiculous, and should be stopped. It is the motor that matters, not the shell it is in!