We used to have a Chevy Quad-Cab Dually with a 454 that we converted to run off propane and gas. It worked great in that huge truck, but I am not sure how well it would work in a sports car. The biggest concern would be the placement of the propane tank. We had ours in the bed of the truck. You should also compare the weight of a filled propane tank to the weight of a filled gas tank. You may want to have a small fuel cell for emergencies and have it duel fuel.