SKYACTIV-R points to Mazda's rotary future

There has been quite a bit of talk recently about Mazda's rotary-powered future, between the RX-Vision Concept and a number of offbeat petrol-electric hybrids.

Although absent in Mazda's range since the RX-8 was withdrawn from sale in 2012, the signature driveline has appeared in Mazda models since the 1970s – and looks set to make a comeback.

Speaking to motoring.com.au at this week's Los Angeles motor show, Mazda's global president and CEO Masamichi Kogai said that although the brand's fan base was heading the charge to revisit the rotary, applications in more fuel-efficient models were also likely.

"Mazda's basic policy is to increase the number of enthusiasts and fans so that when people purchase Mazda – and when they are ready to replace their car with a new purchase – they will come back to Mazda and purchase another," he emphasised.

"Globally there are more than one million people who purchased rotary-engined vehicles in the past, and many of them still own and drive rotary-driven vehicles. Those customers are eagerly awaiting the next rotary-powered vehicle. So for those customers we wanted to show that we are still continuing our development of the rotary engine."

Whether that development forms motive power for the RX-Vision or as a supplementary engine used in conjunction with electric propulsion was unclear, though Kogai-san did hint that it could be both.

"Of course one way to utilise the rotary engine is as a main power source, another option is to utilise it as a power generator or charging the battery as a range extender. And also another area is to directly combust hydrogen as part of the electrification [process] within a hybrid system," he explained.

In any application Kogai-san said the rotary engine – which is expected to be dubbed SKYACTIV-R in production form – will meet ever-tightening emissions regulations, his team tasked with adhering to a brief where efficient, low-emissions and high-output share equal importance.

"Actually, we set very high targets in terms of fuel efficiency and emissions regulation compliance, and also [power] output as well, and our engineers are working very hard," he clarified.

"All our new technologies will be applied and adapted to the rotary engine, although I'm not able to talk about these 'technological menus' at the moment, [I can tell you that] we have lots of new technologies that we are developing."

These technologies may finally include the realisation of the 1.6-litre twin-rotor engine previewed in the 16X Concept of 2007, as well as a single-rotor 800cc unit likely to feature as a range extender in compact petrol-electric models [Mazda has already experimented with rotary power in such a way in its home market where a tiny 330cc single rotor engine was mated to an electric motor in a previous-generation prototype of the Mazda2].

As Kogai-san noted, 'non-performance' applications of the rotary engine is also expected to include a hydrogen burning variant (hydrogen rotary from RX-8 pictured) used to charge the batteries of a cleaner low-volume model for sale in selected markets, or indeed the compression ignition model demonstrated in the RX-Vision Concept.

Mazda has said previously that it may change the shape of its trochoidal rotors or even the rotor housing itself to meet the efficiencies required, however, there's been little discussion around the investment required. Reinventing the rotary engine to meet the requirements of the 21st century may see the project scrapped even before the RX-Vision gets the green light, Kogai-san admitting the backing of his stakeholders was an important consideration.

"The investment requires various elements that we need to think of, and we have to make sure all our employees and also our stakeholders are with us and that they are happy for us to make a decision to go ahead with the rotary engine. Considering all that, then we have to make the total decision [based on] all of those elements before [any] investment," he cautioned.