Sunday, 8 November 2015
Mazda hints at a new rotary sports car
Is Mazda Motor Corporation about to push its rotary engine back into showrooms? Judging by the RX-Vision sports car concept it unveiled at the Tokyo Motor Show, it looks like it is. But when?
Another question: Is the rotary really an engine that can meet the needs of the 21st century with its forthcoming emissions and greenhouse gas requirements? Can Mazda this time solve the issues that led to the downfall of the RX-8 in 2012, namely concerns about fuel economy, emissions and reliability?
Head of research and development, Kiyoshi Fujiwara believes the time is right for the rotary engine to make a comeback. But of course he would say that – Mazda has been working with rotary engines for half a century.
Fujiwara claims: “We want to return the rotary engine to the market someday soon. It’s our heart and soul.”
With the 50th anniversary of Mazda’s first production rotary engine car, the Cosmo Sport coming up the year after next, Fujiwara, adds: “We want to announce something in 2017 – and not a concept car.”
No technical data have been released for the engine in the concept yet, but it is understood it will be a true rotary internal combustion with no electric assistance.
However, turbocharging has to be considered as an option for a production model, with even a hybrid further down the road
Of all the world’s engine makers, only Mazda has remained faithful to Felix Wankel’s powertrain concept for use in passenger cars. One by one the big names have dropped out, with Rolls-Royce in the UK being among the last with its famous ‘cottage loaf’ diesel engine.
If the Mazda rotary is to make a comeback, how have the company’s engineers overcome the principal hurdles?
Fujiwara appears to pin his faith on “advances in technology which will allow for superior efficiency” – always a major criticism of rotary power.
He adds: “We realise the fundamental structural problem of the rotary, but recently new materials have been developed and also some measuring and sensing technology has been updated.”
“We can now analyse the combustion in the engine by computer,” he claims. “And we can control the ignition system or the injection system in the computer, and measure the fuel economy that can occur in the engine. That kind of technology can help us to new materials, a new ignition system or a new shape for the rotary.”
“Hybrid is one future possibility for rotary engines but at first we have to show the rotary engine itself to the fans,” he says. “Two years ago we showed a rotary as a range extender, but some fans complained.”
“The fans said first you have to develop a car with a rotary engine, then Mazda can expand some of the business for rotary engines – that is the request from the fans.”
Mazda executives know only too well that a new rotary-engine car would have to meet strict emissions targets for carbon dioxide and nitrogen oxide, but they are unwilling to speculate on launch dates. And there is little point in trying to please ‘the fans’ until these two chestnuts have been cracked.
Each time in the past Auto Industry Newsletter has quizzed Mazda as to the progress of its new engine, the company says “no comment”, being unwilling to concede even that the engine is still under development.
Given that Mazda has revealed in RX-Vision, the company claims “no decision” has been made as to where a rotary coupe would fit into the company’s product range.
“We haven’t really talked about where the vehicle sits, whether it is going to be more upmarket than the RX-8 or below it,” said a spokesman.
Mazda’s interest in rotary engine technology dates back 54 years to 1961, when it took out a licence and began investigating Felix Wankel’s novel rotary engine concept with a view to the possibility of making the rotary engine commercially available.
However, it wasn’t until 1967 – two years after the debut of the front-engine, front-wheel drive NSU Ro80 at the Frankfurt Motor Show – that the first Mazda production car was unveiled – the Cosmo, with its twin-rotor Wankel rotary engine.
The RX-Vision shown at the Tokyo Motor Show is a sleek front-engined, rear-wheel drive two-seater that points to a possible future range-topping production model.
If a production version does appear certainly it will be welcomed by Mazda “fans” who lamented the RX-8 four-door coupe being axed in 2012.
The RX-8 may have been fun to drive but with a penalty of huge running costs in fuel and oil consumption. To make the “fans” happy, these costs will have to be slimmed drastically.