The Porsche 911 Carrera RSR was the final evolution of the normally aspirated, air-cooled racing 911. It takes the 993 Carrera RS formula and makes it even more track-ready by adding a roll-cage and removing carpet, power windows, and a/c. The RSR was powered by a VarioRam equipped 3,746 cc engine (3.8L) that was convervatively rated at 310hp, driving power to the rear via a six-speed manual. While production numbers are spotty, they are estimated at 45 samples in total.