Mazda rotary: What goes around comes around

MINE, Japan -- Mazda Motor Corp. is moving closer to resurrecting its trademark rotary engine — and it could debut in the United States as soon as 2019.

But don't expect a performance engine sending power straight to the wheels, like in the sporty RX-7 and RX-8 of yore. The next iteration is heading toward an upcoming electric vehicle.

Mitsuo Hitomi, global powertrain head, said the technology will likely do duty as a range-extender engine to generate electricity for the battery-powered car.

"I think that's probably what it will be," Hitomi said during a technology preview at the Japanese carmaker's proving ground here in western Japan.

A rotary engine is ideal as a range extender because it is compact and powerful, while generating low-vibration, Hitomi said. It also gives Mazda a way to keep the technology alive.

Mazda plans to bring an EV to market in 2019, along with a hybrid vehicle.

The EV will come in two forms, said Akira Kyomen, program manager for vehicle development. One will be a pure electric, the other the range extender.

The pure electric will target markets such as Japan, Europe and China, where an EV can get by with a shorter range. But a range extender is seen as necessary for North America and other markets where daily drives are much longer, Kyomen said.

With that strategy in mind, Mazda has developed a vehicle architecture that will debut in 2019. It was designed with a floor pan that can accommodate batteries for an EV or hybrid drivetrain.

Meanwhile, Hitomi confirmed that Mazda's engineers are developing a bigger rotary engine that might someday power a sports car. The biggest hurdle has not been the technology, he said, but making the business case for another performance entry, on top of the MX-5 Miata already playing that role.

The company's question, Hitomi said, has been "whether the business conditions will be met or not … not the big technical issues. Are we going to really sell that many models of sports cars? There aren't that many auto companies selling multiple sports cars."

The rotary engine had been a Mazda bragging point since the company became the first to market the technology in 1967 in its Cosmo Sport/Mazda S110. Mazda's prowess with rotary engines was crucial to its 787B race car, which won the 24 Hours of Le Mans endurance race in 1991, the only victory for a Japanese brand or a car with a rotary engine.

Mazda retired the rotary engine with the RX-8 in 2012 amid slumping sales.

But in 2013, it revived the technology in prototype form as a gasoline-powered 0.33-liter range extender in a Mazda2 hatchback reconfigured to run on an electric motor. That vehicle's name: RE Range Extender, short for Rotary Engine Range Extender.