At the Belgium Spa-Francorchamps 24-hour endurance race in July, four R100 coupes (known in Japan as the Familia Rotary Coupe) started strongly. At the halfway point, the R100 driven by Yoshimi Katayama and Toshinori Takechi held the lead over a BMW 2800 CS, with the other three rotary cars close behind in 3rd, 4th and 8th.
  Then, with only four hours to the chequered flag, disaster struck. One car suffered engine trouble and had to retire. Soon after, a strange noise developed in the engine of Katayama�fs lead car, eventually forcing him to stop. The same problem also ended the hopes of the third car. The final R100 just managed to stave off the engine problems and complete its final lap to scrape through in 5th place.