Mazda is well known for having one of the most prolific factory-backed racing houses, Mazdaspeed. If you visit any nearby track, their claim that "more Mazdas are road-raced than any other car brand on any given weekend" is pretty easy to validate. But did you know that their grassroots style efforts started back in the late 1960s with the Mazda Cosmo?
It’s probably a safe bet that most Oversteer readers have never seen a real live Cosmo outside of their Gran Turismo or Forza garage — even though it was probably a prize car you didn’t actually spend your own money on. However, when the Cosmo was launched in 1967, it was the big dog in Mazda’s lineup.
Importantly, this was the first production Mazda to ever use the Wankel rotary engine in production. Designed by two fellows named Kobayashi and Yamamoto, the Cosmo is a classic from a design perspective. The proportions on this little Mazda coupe are just right: their little 2-rotor engines powered the rear wheels with 110 horsepower, which brought the "110S" designation for cars exported out of Japan. That really wasn’t too bad for a 2000-lb car with a 4-speed manual. So, naturally, someone decided to take it racing.
And where best to test your new revolutionary engine then during an endurance race? That’s correct, the Nurburgring. Looking to test the viability of their new rotary engine, and trying to build from the early sales success of the Cosmo, Mazda went to Germany with two Cosmos. That year, the Nordschleife hosted the "Marathon de la Route," which lasted 84 hours! I see your silly French race, and multiply it by three and a half days!
The 10A series rotary underwent a handful of changes to help with the grueling run around the Ring. A novel side and peripheral-port intake system was added where butterfly valves were switched from the side to the peripheral port as RPMs increased. Inside, the production rotor housing was made of sand-cast aluminum plated with chrome, while the aluminum sides were sprayed with molten carbon steel for strength. Pretty impressive stuff considering this was half a century ago. Cast iron was used for the actual rotors themselves, and their shafts were made of chrome-molybdenum steel. Wasn’t that what Wolverine’s claws were made of. Oh, no? Never mind.
The two Cosmos performed quite well, running fourth and fifth most of the race. It wasn’t until the 82nd hour when one of the cars went out with axle damage. We talk a lot about the reliability of rotaries, much of which is fairly deserving, but this early concept illustrates how well they can perform under stress. The other car, driven by some Belgians, ended up finishing 4th overall. Over the next 15 years, Mazda kept at it — and in 1983, they officially formed Mazdaspeed at the company’s headquarters in Hiroshima.
So how did the Cosmo evolve over time? Well it was updated with a "Series II" the next year that featured more powerful (by 20 hp) 10B engine, power brakes, a 5-speed manual, and some aesthetic updates. Jay Leno owns one, so that says something about it’s significance. The second generation went from 1975 to 1981 and was sold internationally, albeit fairly unsuccessfully, as the RX-5. From 1981 to 1989, the car suffered from a fairly boring design, but made a bit of a comeback in the early 90s as the Eunos Cosmo. Featuring a 20B 3-rotor engine, the Cosmo lived until 1995 and was the top of the line mode of the Eunos luxury brand in Japan and helped make the 20B engine a legend among rotary lovers. You can even find one for sale currently on AutoTrader Classics, as this pretty 1991 Cosmo is listed $15,995. Not a bad price to have the only Cosmo at cars and coffee.
So that’s a quick look at the fascinating motorsports start to a company built much of their image zoom zooming around tracks across the world. It’s time that the little Mazda Cosmo got some credit for helping to launch it all!