The best sports cars have racing in their blood, and Frank Kurtis dominated the Indy 500 in the early 1950s. Bill Vukovich won the 1953 race, and the first seven finishers were Kurtises. In all, 21 Kurtis cars finished in the money, and an amazing 56 entries were Kurtis-Kraft, though not all qualified. Kurtis racers won Indianapolis in 1950, ’51, ’53, ’54 and ’55 and filled out the top 10 places in the other years. The story was the same at all the other tracks across the country.

Frank Kurtis’s creative engineering had spread across the country through his dirt-track sprint cars. They bred a new generation of American drivers who went to SCCA, Indianapolis, NASCAR and Formula 1. He was obviously a force in the racing world, then, but could Kurtis sell a sports car to the public? In 1949, he had already built an aerodynamic two-seater and sold 36 cars before he sold his design to Earl “Mad Man” Muntz, who stretched it into a four-seater that became the Muntz Jet.

In 1951, Kurtis gave it another go and turned his expertise to the Indy 500KK kit chassis with tube frame, solid axles and torsion bar suspension. This could carry a number of fiberglass bodies, from Glasspar, Woodill, Allied and Victress or have the barebones Indy configuration with cycle fenders. Chassis ranged from 88 inches to 100 inches and engines from Ford flatheads to Chrysler’s new Hemi and Cadillac V-8s.

In 1954 Kurtis offered a complete KK, called the 500S, with aluminum body and cycle fenders. 21 were built and proved fiercely competitive, with Bill Stroppe a familiar sight on West Coast podiums. In 1953, he won seven of nine races with a Kurtis powered by a mere 200-hp Mercury flathead, and upsetting a number of Ferraris, Jaguars and Cunninghams. The torsion bar suspension and the Halibrand quick-change rear end could be adjusted for each course, and Stroppe’s luck continued through 1954. But just as he and his partner Clay Smith were gearing up for Le Mans in 1955, Smith was killed in a pit accident, and Stroppe had to sell the car to pay for his funeral.

Looking for a larger market, Kurtis tried a Corvette-like roadster, the 500M, in 1954. This had a fiberglass body with distinctive recessed side panels, often in contrasting colors, and steel panels around the passenger compartment. Only 25 500Ms were sold before production ceased in 1955, as the American public demanded more comfort. The company was eventually bankrupted and Kurtis ceased automotive production in 1957.

Like the famous Allard J2X, Kurtis’s 500S remained competitive and his last model, the SX, was his best. It’s estimated that 12 chassis were completed, with six sold as rolling chassis and four as kits. Four 500SXs were reportedly completed by the factory. They were the final iteration of Bill Vukovich’s 1953 Indy 500 winning chassis, with Halibrand magnesium wheels, disc brakes, Borg-Warner or Jaguar four-speed transmissions and a choice of engines.