I raced the NASA CMC series for years with a Fox body Mustang. It's the most fun I've had in the hobby. You can't go wrong with a 3rd Gen Camaro or a Fox Mustang for road course fun. The Mustangs need springs, shocks, bushings, camber plates, and brakes but they run hard with those changes. Don't worry about the motor, 200-300 horsepower is PLENTY until you really know what you're doing (trust me). If you have a little more to spend, then go C5 Corvette. As others have said, the track days can be relatively affordable. But once you go wheel to wheel competitive road racing, the cost of the car is the least of your worries. I see where USCA is going and I just don't understand why you would risk a big budget PT car when you can run an inexpensive late model under the same rules. Given equal driver skills, you just can't outrun modern engineering with a classic.