16. Pontiac GT-37
One of the rarest and forgotten muscle cars is Pontiac’s GT-37. This was not a model of its own but an option package on the 1970 and 1971 Tempest. Behind this strange name was a regular Tempest with a few performance options. It also the engine from the much more popular GTO model. This meant that buyers who had $3,000 to spend could get a car from 255 HP up to 345 HP.

Pontiac advertised the GT-37 as the “GTO lite.” But the car lacked exterior features like the famous Endura bumper and rear spoiler. For 1971, the famous 455 V8 was offered but went in only a handful of cars. The GT-37 had the performance and the hardware. But it didn’t have GTO’s appeal and image, resulting in awful sales. Pontiac made only around 2000 of these misunderstood muscle cars in two years (via Fosters).