With the slow but eventual death of Mazda's RX-8 in 2012, the Wankel rotary engine fell out of use in road-going production cars. Despite its incredibly simple design — with just three moving parts — it had developed a reputation for being unreliable, oil-burning and fuel-hungry. But a new report out of Japan suggests the rotary, loved by enthusiasts for its distinctive brap-brap sound and driveability, might make a return — in a new Mazda RX-9 at the beginning of the next decade.
This report comes to us from Japanese magazine Holiday Auto via Motoring.com.au, which days that Mazda's board of directors has signed off on the often-rumoured successor to the RX-8 and RX-7 sports cars, approving the research and development and design of a new two-door chassis and rotary engine-powered drivetrain.
Mazda, the magazine says, will use the SkyActiv name — already used for the company's fuel efficient Atkinson cycle piston petrol engines — for the new rotary. The new twin-rotor engine, displacing 1.6 litres versus the older Mazda rotaries' 1.3 litres, may also be turbocharged in the future RX-9, planned for eventual release in 2020 after concept displays at motor shows throughout 2017 onwards.
A rotary engine doesn't use the piston and rod arrangement of a regular motor as used in most petrol and diesel internal combustion engine vehicles on the road today. Instead, a single spinning shaft with a rounded-triangle rotor sits inside an oval housing, moving on an eccentric bearing that creates a constantly-moving combustion chamber where fuel and air are mixed. Trust us, just look at the wiki — you'll understand it straight away.
Mazda had considerable success with its rotary-powered race cars throughout the '80s and '90s, including the distinctive 787B, which housed a 2.6-litre quad-rotor engine. Rotaries have also previously had applications within aircraft and motorbikes for their small size, and have been proposed as range-extender engines in some petrol-electric hybrid cars.