Whirring strangely, a gleaming, otherwordly coupe backs carefully out of a garage filled with legends. The car keeps company with the greats — an Aston-Martin DB4, a Mercedes 300SL Gullwing, a Jaguar E-Type coupe — but it resembles none of them. Its long-tailed proportions are unusual, its details alien. It is more spacecraft than automobile and packed tightly under its skin is a technology that only one company continues to pursue.
The Mazda Cosmo Series I is the very first Mazda model to come with a rotary engine. The prototype was shown at the 1964 Tokyo Auto Show, and just 343 of these cars were built and sold in 1967 and early 1968. Roughly twice as many slightly larger Series II cars followed, both generations hand built at the rate of just two a day.
This example belongs to collector Robert Maitland, who has assembled a selection of 1950s and 1960s cars that each represent a moment of forward-thinking design. The look of the Cosmo doesn’t share much with its well-bred stable mate, but it was certainly as daring in its day as the E-Type or Gullwing. Even better, Maitland’s collection is no mere museum; everything is restored to be driven. His Cosmo wears door decals from a recent 1,600-kilometre classic car rally around some of Vancouver Island’s best twisting roads.
From behind the wheel, the Cosmo’s twin rotary engine emits a strange, combustion-fired warble, and demands high revs to generate its modest 110 horsepower. Yet it is as smooth as a jet turbine as the revolutions climb, and the Cosmo is light, small and deft. The whole is a wonderful car, and endlessly fascinating.
By 1968 standards, this is space-age stuff. However, whether or not you’ve owned a rotary-powered Mazda in the half-century since the Cosmo hit the road, you might be surprised to learn that Mazda hasn’t given up on its unique, internal combustion technology. The company’s latest vehicle, the MX-30 EV, will be available both as a pure EV and with a tiny rotary engine to extend its range.
No other company has ever really bothered with rotary power, and certainly no other mainstream manufacturers champion it today. There were evolutionary dead ends, like the Suzuki RE5 motorcycle or the delightfully named NSU Wankel-spider, but for the most part, trying to perfect the rotary engine bankrupted companies. Not so with Mazda.
A brief primer on how a rotary engine works is needed here. The idea was dreamed up by a German engineer named Felix Wankel, and the technology is properly referred to as the Wankel rotary engine. Essentially, in most internal combustion engines, a piston moves up and down in a cylinder, and vertical forces are turned into rotation by the use of connecting rods and a spinning crankshaft. Think legs pumping on bicycle pedals.
In a rotary engine, curved triangular rotors spin around a rotating shaft, transmitting rotational force directly to the curved combustion chamber in which they are housed. Instead of a bicycle, think of a Catherine wheel firework. Because the rotating mass is now simpler, with fewer moving parts — no need for connecting rods — it is more compact. Further, the firing rhythm of a rotary engine runs much more smoothly than a conventional reciprocating motor.
The problem, unfortunately, can be found at the tips (the apex) of each rotary triangle. Because the Wankel rotary engine is a combustion engine, it needs to have seals that can withstand explosive force, yet not wear out the sides of the peanut-shaped combustion chamber. Many German marques couldn’t figure it out. Mazda did, because they had to.
Mazda licensed the rotary patent from German marque NSU in 1961. Many companies were excited about developing this new type of engine technology, but for Mazda, it was a case of do or die.
In the 1950s, Japan boasted a surprisingly diverse array of auto manufacturers. By the beginning of the 1970s, only the giants remained, given government pressure to consolidate. Toyota swallowed Hino, Nissan snapped up Prince, and both of them eyed tiny Mazda hungrily.
Mazda needed an unparalleled technology to justify its existence as a standalone company. Thus, 47 engineers were assigned to the task of making the rotary engine practical for production. At their head was Kenichi Yamamoto. They called themselves the Shi-ju-shichi-shi, a reference to a legendary band of samurai.
It took six years, but thanks to a breakthrough in materials technology for the apex seals, the rotary engine spun to viability at last. The Cosmo was the first, and began a tradition of rotary sports cars from Mazda, including the mighty third-generation RX-7 of the early 1990s. Perhaps the sharpest-handling mainstream car built by the Japanese automotive industry, this twin-turbocharged monster emerged the same year that Mazda won the 1991 24 Hours of Le Mans race with the triple-rotor 787b. Rotary engines were banned from competing the next year, with race officials citing difficulty in balancing their performance against conventional engines.
But the rotary engine was not just for performance cars. Canada got its first rotary-powered Mazda with the little R100 in 1968. It was more like the contemporary Datsun 210 than the flagship Cosmo, but came with a fizzy 982 cubic centimetre engine that made just under 100 horsepower. Rotary-powered family sedans followed, as did a rotary-propelled pickup, and even a passenger bus.
However, when used normally, rotaries produce considerably more carbon emissions, use more oil and require more fastidious servicing than their conventional rivals. When the RX-8 exited the market in 2012, tears were shed by few other than the most faithful rotary fans.
Yet, Mazda persists in trying to make the rotary work in the modern age. For more than 50 years, the technology has been a core part of the company’s identity. Further, the rotary’s high operating efficiency and compact size could make it the ideal range-extender for electric vehicles, perhaps than the motorcycle-sourced engines used by BMW. Running as a generator only in a narrow, efficient powerband allows Mazda to tune its rotary for minimal emissions.
If nothing else, Mazda’s commitment to the rotary shows a loyalty to company heritage. The story of the rotary engine began with cars like the Cosmo. Mazda isn’t yet willing to close the book on it.