Mazda's long-awaited new RX rotary coupe to take centre stage in less than two weeks

Two weeks ago Mazda announced it would stage the world debut of something special at this month’s Tokyo motor show on October 28, releasing a single teaser image highlighting the roofline of the mysterious “sports car concept”.

Speculation about the car’s identity focused on two possibilities: a hard-top variant of the new MX-5 roadster, which has now been ruled out until later next year, or a concept previewing Mazda’s hotly-anticipated new-generation rotary-powered sports coupe widely expected to be called the RX-9 – just as we predicted it would last month.

We now have it on good authority that Mazda will in fact unveil its long-awaited replacement for the RX-7 and RX-8 rotary coupes, following a ‘steer’ pointing to another car on Mazda’s Tokyo stand by a source close to the Hiroshima car-maker.

“Look to the Cosmo Sport,” was the cryptic reply to questions about the concept’s significance.

Debuting in 1967 and also known as the 110S, the radical Cosmo Sport was the world’s first mass-production rotary coupe — even if Mazda only made 1519 of them — and has been confirmed to sit right alongside the unnamed concept at the show.

“The Cosmo has no earthly reason for being there unless…,” nodded our insider, before stopping mid-sentence. Unless, of course, a born-again rotary coupe is also revealed.

“The design of the sports car concept to be unveiled in Tokyo is modern but maintains a sense of lineage and authenticity, appearing almost to condense Mazda’s entire history of sports car development into a single model,” said Mazda on September 30.

Mazda executives suggested earlier this year that they would like to celebrate the Cosmo’s 50th anniversary in 2017 with an all-new rotary model, and have always insisted rotary engine development was ongoing.

Employing peculiar Ferrari-like lines, the rendering you see here takes the teaser image published by Mazda and adds a front-end inspired by the company’s latest Kodo design language.

Mazda’s last rotary car, the 1.3-litre RX-8 four-door ‘coupe’, went out of production in 2012. The RX-8 was a blast to drive and revved to 9000rpm, but lacked mid-range torque and consumed too much petrol and oil.

To address those issues, our sources say Mazda is currently testing a new hybrid turbo rotary powerplant previously referred to as the ‘16X’ and boasting a twin 800cc rotor set-up expected to generate upwards of 335kW.

It’s expected to do so with the assistance of a capacitor-powered electric turbocharger, but it’s unclear whether Mazda will also apply the range-extending technology trialled in the previous-generation Mazda2/Demio EV concept, which would make it a plug-in hybrid.

As we reported earlier this year, Mazda engineers are working on a two-stage turbo system that incorporates an “electric turbo assist” function that engages at low rpm and a standard exhaust-driven turbo that cuts in at higher revs.

According to our sources, driving the e-turbo will be a capacitor (a unit that stores power and discharges it on demand) to beef up the rotary’s ‘instability’ at low rpm, while a conventional exhaust gas-driven turbocharger will engage to keep the flow of power coming as boost rises at higher revs.

To improve fuel economy and emissions, Mazda will incorporate homogeneous charge compression ignition (HCCI), which as we’ve reported will be the centerpiece of the second-generation SKYACTIV powertrain suite that will power the company’s seventh-generation model range also due to appear around 2017.

Mimicking the diesel combustion process in a petrol engine, HCCI retains spark ignition at low revs but employs compression to ignite the fuel/air mix at higher revs, increasing combustion efficiency and emitting lower levels of Nitrogen Oxide (NOx).

Unlike many car-makers that have tried but failed to implement HCCI technology in production cars, Mazda is confident it can overcome the pre-ignition or ‘knocking’ problems associated with HCCI technology.

So it appears everything is fitting into place for Mazda, which will also stage the domestic debut of the KOERU concept that previews next year’s all-new coupe-crossover to be called the CX-4 or CX-6.

The bad news is the KOERU and ‘RX-9’ have pushed to the backburner the rebirth of Mazda’s MPS performance brand, which is now unlikely to reappear until next decade.

So we wait with baited breath to see whether the concept car at Tokyo in two weeks points to a production version to mark the Mazda rotary’s 50th anniversary in 2017, or whether we’ll have to wait for Mazda’s centenary in 2020 for a born-again RX-7.