The Lotus 56, powered by a turbine engine, was designed for the Indy 500. Three exemplars were entered in the 1968 edition, finishing in the top twenty with Joe Leonard, Art Pollard and Graham Hill after showing promise during qualifying. The engine was a Pratt & Whitney that could develop, according to the fuel, from 430 to 550 horsepower. The Granatelli brothers, the main sponsor of the team, who had wanted this very unusual engine, thought that this technical innovation would attract the attention of the media. And that's what happened, even though the Lotus 56 was never really a winner. Lotus also attempted to apply it in Formula 1 with poor results.