It was with Pontiac that Yunick became the first team owner to win the Daytona 500 twice (1961 and 1962), and first to put a driver, his close friend Fireball Roberts, on the pole three times (1960–1962); this also made Pontiac the first manufacturer to do so. Following Fireball Roberts' 1964 crash at Charlotte — where after 40 days in pain from burns, he died — Yunick began a campaign for safety modifications to prevent a repeat of such disasters. After being overruled repeatedly by NASCAR's owner, Bill France Sr., Yunick left NASCAR in 1970. As with most successful racers, Yunick was a master of the grey area straddling the rules. Perhaps his most famous exploit was his #13 1966 Chevrolet Chevelle, driven by Curtis Turner. The car was so much faster than the competition during testing that they were certain that cheating was involved; some sort of aerodynamic enhancement was strongly suspected, but the car's profile seemed to be entirely stock, as the rules required. It was eventually discovered that Yunick had lowered and modified the roof and windows and raised the floor (to lower the body) of the production car. This car has many legends about it, and they were definitively debunked by the 2019 Dinner with Racers episode on Amazon Prime TV. Since then, NASCAR required each race car's roof, hood, and trunk to fit templates representing the production car's exact profile. Another Yunick improvisation was getting around the regulations specifying a maximum size for the fuel tank, by using 11-foot (3 meter) coils of 2-inch (5-centimeter) diameter tubing for the fuel line to add about 5 US gallons (18.9 liters) to the car's fuel capacity. Once, NASCAR officials came up with a list of nine items for Yunick to fix before the car would be allowed on the track. The suspicious NASCAR officials had removed the tank for inspection. Yunick started the car with no gas tank and said "Better make it ten," and drove it back to the pits. He used a basketball in the fuel tank which could be inflated when the car's fuel capacity was checked and deflated for the race. Yunick also used such innovations as offset chassis, raised floors, roof spoilers, nitrous oxide injection, and other modifications often within the letter of the rule book, if not the spirit. "All those other guys were cheatin' 10 times worse than us," Yunick