Mazda will debut the SKY-G, SKY-D and Sky-Drive concepts at the
Tokyo Motor Show in October. Contrary to their names, though, they're not a Mazda soiree into the world of aeronautics, rather a pair of efficient engines and a new automatic transmission.
The 'Sky' thing is the theme under which Mazda will be operating at the Tokyo show, emphasising its commitment to all things green and pleasurable in the future - or 'elevated driving pleasure together with outstanding environmental and safety features,' as the Japanese maker puts it. It's off to a good start, as the Sky tech will all be wrapped up in the very juicy Kiyora concept.
SKY-G is a petrol engine (G stands for 'gasoline') and SKY-D is diesel. The petrol one is a direct injection 2.0-litre unit that boasts 15 percent more torque and fuel economy than the current 2.0-litre petrol engine thanks to variable valve timing and a block redesigned to reduce mechanical friction. The SKY-D diesel has similar friction-reducing refinements, reshaped combustion chambers and new 'piezo' fuel injectors combined with a two-stage turbocharger. Consumption is 20 percent lower than the current 2.2-litre diesel, we're told.
The Sky-Drive transmission is, we're promised, five percent more economical and more satisfying to use than Mazda's current torque converter automatic, apparently being similar in feel to a dual-clutch auto. Again, reducing mechanical friction is the key improvement.
The Kiyora concept set to hit Tokyo is equipped with a 1.3-litre SKY-G engine linked to a Sky-Drive auto transmission that give the rakish concept an astonishing 91.1mpg fuel economy figure. That's using a Japanese test cycle, mind. Also helping achieve that is a start-stop engine system (called i-stop in Mazda guise), regenerative braking and aerodynamic improvements.
Mark Nichol - 29 Sep 2009