5. Chevrolet Aerovette XP-895
Chevrolet dabbled with Rotary powered vehicles in the 1970s, but none ever made it to production. After first building a two rotor motor to test in the Vega compact car, Chevrolet decided to bolt two of these engines together and create a 420 hp four rotor motor. The manufacturer created this monster for the Chevrolet Aerovette XP-895; a mid-engine potential super-Corvette.
However, due to the fuel crisis and financial costs, the rotary program was scrapped at GM and the four-rotor motor was replaced by a conventional V8 in the Aerovette. The Aerovette would follow the four rotor a few years later and be scrapped as well.