The Rondeau M379B was a development of Jean Rondeau's project which dated back to the first Inalteras of 1976. The car, a sports prototype with a 3.9-litre Ford Cosworth V8 engine, was entered in the 1980 24 Hours of Le Mans with two official examples in Group 6 and a third chassis in GTP class. It was in that race that the constructor Jean Rondeau, together with Jaussaud, achieved an exceptional victory, beating the Porsche 908/80 of Ickx/Barth and going down in history as the first (and still the only) winning constructor at Le Mans at the wheel of his own car. The M379 was updated again for 1981, and from 1982 Rondeau built cars compliant with the new Group C regulation.