Smokey Yunick's 7/8 '66 Chevelle is the classic NASCAR cheat story. It's on the Wikipedia page here: https://en.m.wikipedia.org/wiki/Smokey_Yunick https://en.m.

Smokey Yunick's 7/8 '66 Chevelle is the classic NASCAR cheat story. It's on the Wikipedia page here: https://en.m.wikipedia.org/wiki/Smokey_Yunick https://en.m.wikipedia.org/wiki/Smokey_Yunick He basically scaled down a car's dimensions to make it lighter while still looking similarly to the full size version. This made NASCAR introduce jigs to measure the cars. A rule that is still very much in use.