The Monte Carlo SS with the curved back windshield was the Aerocoupe SS. The back glass was curved to help reduce drag. It did reduce drag but not by a lot. It only reduceded drag by about 2.7 percent. This gave you about an extra 5 mph on the track. The Aerocoupe was only made in 1986 and 1987. Only 200 of them were made in 1986 so they are very rare. There were 6052 Aerocoupes made in 1987 which made them a little easier to get. Chevrolet was supposed to build up to 20,000 Aerocoupes. They did not say why, the never made the full 20,000. In my opinion, the regular Monte Carlo SS looks a little bit better than the Aerocoupe. The regualr SS is lighter too.