Reventlow began his racing career in America in the mid-1950s, initially with a Mercedes before moving to an 1100cc Cooper in 1956. The next year he went to Europe to buy a Maserati, which he crashed heavily at Snetterton, escaping unhurt. He also briefly drove a Cooper Formula 2 car, before returning to the United States. He then set up his own company in Venice, California, to construct Chevrolet-powered race cars he named Scarab with Phil Remington as chief Engineer. Along with hired driver Chuck Daigh, the two were initially successful in racing. They won the majority of major sportscar events they entered, often in competition with the Cunningham team of Lister Jaguars. Reventlow had looked at buying a Lister Jaguar, but thought that he could build a better car. Daigh drove a Scarab to victory in the 1958 Riverside International Grand Prix in California, beating a field of international race car teams, including the world-famous race car driver Phil Hill and the Ferrari Team. Carroll Shelby drove a Scarab to first place at Continental Divide Raceways in Castle Rock in Douglas County, Colorado, where he broke a course record.