38. Chevrolet Camaro ZL1
In the late ’60s, Can-Am was a famous racing series and it featured prototype class cars with V8 engines. Chevrolet wanted to purpose-build a power plant for this championship and produced an all-aluminum 427 big block called ZL-1 in 1969 (via Motor Trend).

It was a high-revving, 7.0-liter V8 with around 550 HP. Chevrolet produced about 200 of those engines. While most of them went to Can-Am racing teams, 69 ZL-1s were installed in C.O.P.O. Camaros and sold to drag teams. The Camaro ZL-1 was totally the same as the regular 1969 Camaro on the outside, but it was so fast it was barely street legal.