The Mazda 787 and its derivative 787B are Group C sports prototype racing cars that were developed by Japanese automobile manufacturer Mazda for use in the World Sportscar Championship, All Japan Sports Prototype Championship, and the 24 Hours of Le Mans from 1990 to 1991. Designed to combine a mixture of the Fédération Internationale du Sport Automobile (FISA) Group C regulations with the International Motor Sports Association (IMSA) GTP regulations, the 787s were the last Wankel rotary-powered racing cars to compete in the World and Japanese championships, using Mazda's R26B engine.
Although the 787 and 787B lacked the single lap pace of World Championship competitors such as Mercedes-Benz, Jaguar, and Porsche, as well as Japanese Championship competitors Nissan and Toyota, the 787s had reliability that allowed them to contend for their respective championships. The reliability of the cars eventually paid off in 1991 when a 787B driven by Johnny Herbert, Volker Weidler, and Bertrand Gachot went on to victory in the 1991 24 Hours of Le Mans. As of 2018, this remains the only victory by a car not using a reciprocating engine design, a record likely to never be repeated due to regulation changes until recently. For the 2020-2021 season a new FIA Prototype Hypercar class will now allow a Rotary engine under the NSU Wankel patents. It was the first victory by a Japanese manufacturer, and the only such victory until Toyota won the 2018 24 Hours of Le Mans.