The IMSA Audi 90 GTO was one of the wildest, most technologically advanced four-door race cars to ever hit the tracks. It was basically a 700bhp AWD Group B rally car engine-drive train package, mated to a space frame chassis, and draped with a carbon fiber silhouette body. It featured a 2,190 cc / 133.6 cu in 5 cyliner engine pushing 709 bhp / 529 kW of power @ 7,500 rpm and 720 Nm / 531 ft lbs of torque @ 6,000 rpm. Thers were only 6 ever built.