How Mazda's 787B Won Le Mans With an Engine Already Slated for a Ban

When Johnny Herbert crossed the finish line at Le Mans on June 23, 1991, he was driving one of the best race engines ever built, an engine that had essentially already been banned. The Mazda 787B's four-rotor R26B was the last rotary-powered car to race at Le Mans, and the team knew beforehand that 1992 regulations would make the engine ineligible.

The win came down to regulatory timing, a grandfathering clause, and a small but critical amendment that Mazdaspeed's team principal pulled from the governing body. Rotary engines weren't explicitly welcomed under the era's rules; they fell into a category of unconventional powerplants treated with growing skepticism through the late 1980s.

By the 1992 season, FISA had made clear rotaries would no longer be permitted at Le Mans.

The 787B was grandfathered into the 1991 race under existing rules before the ban took effect. Mazdaspeed had campaigned rotary cars at Le Mans since the 1970s, with the factory effort starting in earnest in 1983. The 1991 race was the final window.

A new regulation required competitors to add ballast, which would have hurt the 787B's performance. Team principal Takayoshi Ohashi secured an amendment from FISA allowing the car to run in standard configuration while rivals added weight. It was a small victory, but in endurance racing, small advantages add up.

m. on the first evening. By mid-race it was third, and with three hours left it sat second when the leading Mercedes-Benz retired with engine failure. The number 55 car completed 362 laps, needing just one oil top-up, new brake discs and pads, and one nose replacement across 28 pit stops.

The 700-horsepower four-rotor proved the most reliable machine on track.

The victory was the first overall Le Mans win for a Japanese manufacturer and cemented the rotary's place in endurance history. It also set the stage for future Asian competition, including Genesis Magma Racing's successful debut.