Mazda6 & SkyActiv technology

I’ve just stepped out of a Mazda6 that had no active stability control, ABS or airbags, the interior had been roughly cut and modified to the point it resembled a stolen car, and the exterior had additional body work riveted on like the poxiest of boy-racer modifications.

Hard to believe it’s worth – conservatively – almost half a million dollars.

This is no street car hotted up to fast and furious proportions, nor is it an out and out race car. It is, underneath the altered skin, a factory test ‘mule’ of the next Mazda6, still years away from production.

The model of car isn’t actually important, but the innovation it has at its core however is.

New Zealand will see Mazda’s new SkyActiv technologies filter through to models later this year in the form of a newly-developed petrol engine and automatic transmission, but this rough as guts pre-production vehicle expands on SkyActiv initiatives to give an insight of what’s around the next corner. That includes the impressive new diesel engine I’m sampling today and that will also arrive before long, but also new chassis and suspension designs. SkyActiv is more a total car philosophy than pet term for a new environmentally-conscious fuel injection system.

Punting it through the essess of Melbournes Sandown raceway is telling of the Mazda’s future product; already near the top of the food chain dynamically, the significant weight saving in both sprung and unsprung mass are evident. Despite a stiffer and bulkier new ‘trident’ chassis rail design a massive 140kg has been shed from the existing Mazda6 and you can feel every ounce of it. The steering feels light and almost certainly still requires final calibration and finessing, but it is so direct with the beautiful combination of large car stability in high speed corners, with the front-end turn-in response of a small hatch.

No official performance figures have been released but the new SkyActiv diesel outperforms our current petrol version convincingly. Sandown’s an open, high-horspower track where taller gearing and plenty of gusto under the bonnet wins races. Down the back straight the diesel test mule was seeing 10-15 km/h more on the speedo than the petrol car and rapid shifting of the new transmission matched the fast revving diesel well.

It’s no dual clutch arrangement as we see in Volkswagen models, but the six-speed auto does flick through the ratios with almost the same haste, a more sympathetic soft shift calibration the only perceivable difference between the cost DSG-style product from Europe.

And keeping costs down is important, Mazda’s head of product planning and powertrain development, Kiyoshi Fujiwara, says he remains conscious of where Mazda sits in the market. Start to load up with expensive innovation and the car becomes unattainable for Joe Public. By focussing on vastly improving the design and operational parameters of the petrol and diesel engine internals,instead of prematurely spending money on things like hybrid technology – which is still at a premium – Mazda has achieved acceptably low emissions for the category they occupy, and strong performance without making the car more expensive.

That’s not to say it’s not innovative. The new combustion chamber and piston design, along with revised injection protocols, mean bulky and costly exhaust recirculation systems that have been mandatory for decades can now be thrown away. It’s all about improving the basics, which if you ask any performance engine builder, is fundamental to everything: efficiency, durability, throttle response and eventual output. Key improvements are around reducing mechanical and pumping losses: the pistons, connecting rods and crankshafts are all dramatically lighter, they change direction faster so the engine revs much faster. Drill down further into what is a an epically long list of technical tweaks, and you’ll see the piston rings have a lower tensile force, the crank journals are narrower ,and the compression ratios are radically different at 14.0:1 on both petrol and diesel variants. For the layman, that’s very high compression for a petrol (which vastly improves fuel economy and emissions) and unusually low for a diesel (which makes for an uncharacteristically lively, rev-happy engine).

In the short term expect the first wave of SkyActiv petrols and the new transmission to be quieter, smoother and much more efficient, but the real revelation will be when Mazda NZ finally bring the European-rivalling diesel to market a little later, and when those weight-saving measures start to filter through from pre-production to the showroom floor.

See used Mazda6 for sale.