UNKNOWN — Late-1950s:  Carroll Shelby next to a 1958 Pontiac Chieftain, part of a new group of cars that the Pontiac Division of General Motors were promoting as their new “muscle” cars.  In 1958, Shelby actually raced a Maserati 450S equipped with an engine out of one of these Pontiacs in several sports car races.  Shelby went on to the biggest win of his career the following year in taking the 1959 24 Hours of Le Mans at Circuit de la Sarthe in France, co-driving an Aston Martin with Roy Salvadori.  After retiring as a driver, Shelby was best known for making the AC Motors-based Shelby American Cobra and later, starting in 1965, Ford Mustang-based performance cars for Ford Motor Company known as Mustang Cobras. His company, Shelby American Inc., founded in 1962, still sells modified Ford vehicles, as well as performance parts.  (Photo by ISC Images & Archives via Getty Images)