Watch Mazda rebuild a 4-rotor race motor from the 787

It’s no small undertaking to rebuild a 4-rotor R26B from a Mazda 787 race car. Most of the parts are unique to the engine and have been out of production for decades. A recent Mazda Motorsports video shows what it takes to tear down one of these epic race motors and rebuild it so that Mazda’s 787 can continue to share its unearthly roar with fans.

Ed Senf, who oversees electronics and engine management of the Mazda Heritage Collection, describes how nearly every piece of the R26B was unique to the racing program. Mazda made a finite number of parts, enough to carry them through the Le Mans and Group C program, and that was it.

The eccentric shafts are unique to the motor. The housings have three spark plug ports instead of two. The only piece that’s swappable with a modern Mazda motor is the rotor itself. Fortunately, the technicians were able to reuse the main components and source what needed to be replaced.

In the video Mark Raffauf, Senior Competition Director at IMSA, shares a great anecdote about the Mazda 4-rotors:

The Japanese team decided one year it would be a good idea to test at Daytona, high speed before going to Le Mans. [They] brought the whole team and two cars over to Daytona and at the time I was the president of IMSA and we were based in Tampa. John Cooper was the president of Daytona, and the phone rings one day and he’s all, “Raffauf, it’s Cooper.”

“Yeah. Hey John, what’s up?”

He says, “What the hell is in those cars?”

I go, “what do you mean?”

And he goes, “The paperwork on my desk is vibrating around across the surface of my desk. And we have people who live on the beach [complaining].”

Every once in a while, people complain about noise out of the Speedway, but never from the beach, which was like four miles away, 4 and a half miles away. You knew it was
something else.

Mazda has undertaken a a years-long project to restore its entire fleet of race cars from its North American heritage collection. The work is being carried out by Flis Performance of Daytona Beach, Florida, builders of the Mazda MX-5 Cup cars. Hopefully we’ll see videos like for the other cars that are being restored.