When NASCAR was formed in 1948, the first season was filled with races featuring older, modified coupes from the prewar era. But when “Big” Bill France envisioned a stock car series, he wanted the cars on his racetracks to be real, stock cars. The rules were fairly simple for the first “strictly stock” season of ’49, stating that both the car and engine had to be available to the public. Racers, as they do, pushed the boundaries of the rulebook, eventually leading to homologation rules that stated manufacturers must sell a certain number of a car or engine to make it legal for competition. The number fluctuated over the course of the rule’s lifetime, larger or smaller when convenient to encourage competition (and manufacturer dollars) and sometimes determined through a formula, but 500 units was a rough average.
The fastest street cars made the fastest race cars, and machines like the 1949 Oldsmobile with Rocket V-8 power and the low-slung, aerodynamic Hudson Hornets of the early 1950s dominated. But there was clearly a cat-and-mouse game between NASCAR and manufacturers, both in an effort to control speeds and level the playing field. During 1957, NASCAR outlawed the use of “exotic and multi-carburetor induction systems,” which effectively outlawed the famed “Black Widow” Chevy, and the E-code and F-code Ford engines, for example. By the 1960s, as the street performance game was really heating up, wins on the NASCAR circuit meant sales in the showrooms, so many manufacturers were really pushing the rules, and France wasn’t enforcing his homologation regulations as strictly as he once was. In 1962, Pontiac’s championship-winning Super Duty 421 Catalina, for instance, wasn’t exactly homologated. Nor was Chevy’s “Mystery Motor” or Chrysler’s 426 Hemi, which dominated the 1964 season. These engines weren’t available at any dealership
.After the Hemi blew everyone’s doors off, and following the deaths of three superstars, Bill France laid down the law once again. Starting in 1965, NASCAR implemented rules dictating that all engines conform to a maximum displacement and be of a production design only, and only a single, four-barrel carburetor was allowed. There were several more details and updates to the rules and it all meant the free-for-all was over. To get extra speed on the track automakers quickly began creating homologation specials – street cars with sleeker aerodynamic bodies and more powerful engines to increase their performance. Here, we’ve chosen our 10 favorites and listed them in chronological order.