Smokey Yunick, pictured here at the 1967 Daytona 500, really knew his way around under the hood of a car.

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The Gray Area

­NASCAR used to be a lot less stringent when it came to inspecting cars, as well as regulating and banning certain car components. In the old days, trying to figure out ways to get more speed out of a car was the name of the game. Mechanics were always experimenting and innovating. If the slender rulebook didn't expressly forbid, then anything they could dream up was fair game. Of course, one rule could always still get in their way -- old 12-4-A which includes "Actions detrimental to stock car racing" -- a catchall that was often pulled in a pinch. Whether you prefer to label a particular action cheating or being creative is a call we'll leave up to you, but let's start out by taking a closer look at some of those examples from the early years of stock car racing.

­Cars have to weigh in at a certain minimum weight in order to race -- too light, and they can give an unfair advantage to that driver. Once, Smokey Yunick reportedly used wet sand to reach the necessary inspection weight. When the sand had dried the next morning, it was easy to pour out and lighten the load. Another time, he asked to borrow one of NASCAR's templates (apparatuses used to measure racecars' size and shape), but instead of checking to see if his vehicle was correct, he modified the template and scaled it down. Unfortunately for him, another driver unexpectedly showed up with a car of the same make and model and Smokey was busted [source: Caraviello].­

Some of the other plans teams concocted back then included lightweight aluminum frames and fiberglass hoods, engines injected with nitrous oxide for a little extra pep, tires loaded with weights that boosted the car up to the minimum requirement but could then be swapped out for lighter pair at the first pit stop -- you name it, they tried it.

­But the story doesn't end here, go to the next page for examples of more modern occurrences that some label cheating, others inventiveness.