Shelby GT500 Super Snake
This GT500 Super Snake was produced as a rolling laboratory to showcase the possibilities of the Mustang platform as well as for testing Goodyear’s “Thunderbolt” tire line. Goodyear was proud to announce that their Thunderbolt tires are capable of running at 170 mph, and Shelby was quick to build a car capable of that speed. Using a Le Mans-winning race engine and modifying the transmission and suspension, Shelby created the Super Snake, the ultimate 170 mph Mustang. Even though today, 170 mph isn’t that uncommon top speed, back in the late ’60s, most muscle cars struggled to reach 120 mph (via Supercars).

However, Super Snake debuted in 1967 and broke several production car records with Shelby himself behind the wheel. In fact, Super Snake was so successful that there were production plans, but when Shelby realized that the finished product price would be around $8000 (big money for 1967), he killed the project because he realized that nobody would buy the car.