Lunger joined the Hesketh Racing Formula One team in 1975 for the running of the 1975 Austrian Grand Prix. Aside from Mario Andretti and Mark Donohue, he was the only American driver on the elite circuit. At the age of 29 Lunger found himself without a car to drive for a major team. His friends bought him a ride with the team of Alexander Hesketh, 3rd Baron Hesketh for the remainder of the 1975 Formula One season. Lunger's brother, Dave, and Rod Campbell, a veteran motor racing public relations man, formed a combine in late 1975 to promote a Formula One ride for Lunger. In his debut Lunger started from the 9th row. He finished 13th in his Hesketh-Ford. In qualifying for the 1975 United States Grand Prix, Lunger wrecked his Hesketh, sustaining superficial damage to his car. He recovered to become one of 24 qualifiers for the race. Lunger ran as high as 8th at Watkins Glen, before he retired. In the 1975 Italian Grand Prix he came in 10th.