2012 MAZDA6 SKYACTIV REVIEW
It's a vision of things to come from Mazda - its SkyActiv technology. For Mazda engineers, it's a holistic search for increments; for finding improvements at the margins across the whole of the vehicle and its base technologies.
It not only means lighter, more responsive and more fuel efficient engines - both petrol and diesel - but new transmissions, aerodynamics, metallurgies and management systems.
As Mazda Australia MD Doug Dickson said, SkyActiv embodies "the technologies that underpin the next generation of Mazda products".
"(Mazda) is not relying on super-efficient hybrids to achieve what has to be achieved (in fuel efficiency gains and emissions). It has cracked the combustion efficiency problem in a way that does not require expensive technologies," he said.
Enough of that, how does the new SkyActiv technology perform in the 'almost-real' world of a prototype on a race track?
We got behind the wheel of a $300,000 prototype of the next-gen Mazda6 fitted with the 'SkyActiv-D' diesel and 'SkyActiv-Drive' six-speed auto.
It looked like the current 6, kind-of: pop-rivetted metal sat over a redesigned suspension and lightweight body. Although marginally longer than the current Mazda6, and on a wider track, it shaves more than 100kg from the current car.
Quite simply, it drove like no other diesel of my recent experience. Lighter on the inside - conrods, crank, pistons, skirts - and out, and with a compression ratio of just 14:1, the SkyActiv-D diesel spins as readily and effortlessly as a petrol engine. '
And, from outside the car as well as in, there is barely a hint of diesel clatter.
Interestingly, while the SkyActiv-G petrol engine has a high compression ratio to deliver better thermal-efficiency, fuel economy and improved low-end torque, the diesel takes the reverse tack. Its significantly lowered compression ratio helps optimise injection timing as well as reducing mechanical friction, also resulting in better fuel economy, emissions performance and efficiency.
Under the toe, the diesel prototype feels fast, accelerates strongly, delivers a shoeful of torque from very low down, and spins freely to its 5200rpm redline.
The low-friction SkyActiv transmission, with a lock-up clutch that locks up the torque converter at relatively low speeds, gives the prototype a direct-drive feel and a throttle response lacking in conventional autos.
Through the tight left hander at the bottom of Sandown, and the 'technical' tight right then sharp left that follows, the SkyActiv-D Mazda6 can be kept right on the nail.
It is a beautiful drivetrain, 2.2 litres, twin-scroll turbo, 136kW and a whopping and very eager 420Nm of torque. Mated to the six-speed auto, with crisp decisive changes, it pulls like a train and is a very potent unit.
Down below, the SkyActiv suspension and chassis changes are also apparent. Tested side-by-side with a current-gen Mazda6 diesel manual and petrol auto, the 2012 Mazda6 sits flatter, turns in more eagerly, feels more rigid (rigidity has been improved by 30 percent despite the lighter body), and leans less on the front outside wheel in fast cornering.
It is also more stable during high speed straight-line direction changes - slapping it through a 'chicane' it takes a tighter line with considerably less weight-transfer on exit.
So, yes, Mazda's new SkyActiv 6 promises to be an interesting car. The SkyActiv-D we drove is a diesel for someone who may never have considered a diesel, and an auto for the avowed manual driver.
If this really is the feel of the next Mazda6, it is going to win a bucket of friends. With up to 20 percent improvement in fuel economy, it will also save them a lot of money at the bowser.