Pole sitter Mario Andretti (USA) Lotus 78 went on to win the race. Unbeknownst to most at the time, the Lotus 78 featured sliding skirts that were in constant contact with the ground, providing Mario Andretti (USA) with a significant cornering advantage, which was most obvious during qualifying.
French Grand Prix, Rd 9, Dijon-Prenois, France, 3 July 1977.
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