Mazda Ice Academy: AWD test

The mother of all snow storms made conditions absolutely diabolical for motor vehicles of any kind – but the timing couldn’t better for the inaugural Mazda Ice Academy in Colorado this month.

Mazda's thinking was thus: use low-friction surfaces to emphasise the capability of its seldom-discussed all-wheel drive (AWD) system, dubbed iACTIV.

Mazda reckons its iACTIV part-time AWD system is more proactive in its initiation and generally better than its Japanese rivals, due to its ability to interpolate more data via a multitude of sensors.

Indeed, the company wasn’t shy about boasting how its part-time AWD system is better than Subaru's.

With the snow storm raging outside – it was so severe it shut down airports and forced cars off the road – and temperatures dropping to almost 20 degrees centigrade below zero, it's explained that we'll undertake a number of exercises on a specially created private snow and ice course designed to test the AWD systems.

Long story short? Both the CX-3 and CX-5 performed well in the treacherous conditions -- far better than expected.

There were a number of elements to the Ice Academy, including thrashing an MX-5 around an autocross track (stay tuned for that one) and testing the difference between all-season and winter tyres on a CX-3.

However, the most instructive test was the hill start and slalom course, which provided the opportunity to benchmark the Honda CR-V, Subaru Forester and Mazda CX-5, back to back.

SLALOM TEST
Off the mark, the CX-5 accelerated slightly faster than its rivals, then each vehicle was pushed to around 27mph (43km/h) for the slalom course, where the Mazda performed better than the other two in rapid changes of direction, left to right.

The slalom run ended with a wide, sweeping right-hand bend designed to test the vehicles' ability to hold a line through a low-grip corner.

We had two runs in each of the three vehicles, back to back, but realistically Mazda would never have offered the media the Subaru and Honda as yardsticks if it knew the result was not going to be in its favour. As such, tests like these are always fraught with inconsistencies and variables.

But for what it's worth, on the day, the CR-V was the least confident in the treacherous, low-grip conditions.

The Honda understeered into the first turn of the slalom, its electronic stability control system intrusive to the point where throttle and steering response achieved little. It could corner only at single-digit speeds.

Of the three SUVs on test, the CR-V felt the most nervous and had the least grip, ploughing its front-end wide when its throttle was applied though the final 180-degree sweeping corner.

The second vehicle we tested was the CX-5. Compared to the other two it had more communicative steering, so you had a better idea of what the front-end was about to do. It felt less clumsy than the CR-V, exhibited the least understeer of the trio, instilled the most confidence and was fastest through the slalom.

Simply put, it felt more in control than the CR-V and relied far less on its stability and traction controls to maintain its trajectory. It also rounded the final sweeper corner with more confidence, and this was where you could feel AWD system working most clearly.

We expected the Subaru to be the most capable in the conditions, and after reaching 27mph the Forester felt tight initially, much like the CX-5 into the first corner. But in the second slalom corner, as it changed direction, it lacked the stability of the Mazda, ploughing forward with understeer and unable to maintain its intended direction.

The rest of the slalom had to be taken slightly slower and with more caution as a result.

The Forester wasn't as untidy as the CR-V, but wasn't quite as sharp as the CX-5. It also didn't have the poise of the CX-5 through the final sweeping corner, but it wasn't far off.

Bear in mind the Forester tested here features a part-time AWD system similar to the other two cars, as it was equipped with a CVT automatic transmission and not the seamless, full-time AWD system of manual-equipped Foresters.

HILL START TEST
The second test involving the three Japanese mid-size SUVs was a hill start test, for which we were tasked with stopping on an incline, turning the wheel to the right and attempting to pull away.

Interestingly, it was the Forester that seemed to struggle the most with this one, with outside observation revealing the vehicle's unwillingness to divert torque to the rear wheels on its first attempt. It fared slightly better on its second and third attempts.

Meantime, the CR-V had virtually no trouble, and neither did the CX-5.

What does this prove? Well, apart from the CR-V's return to form, it showed which vehicles were most willing to adapt to the challenging conditions, whether it was changing direction at speed or a standing start with the wheels turned.

Dave Coleman, development engineer at Mazda North American Operations, summed up Mazda's iACTIV AWD system like this: "We want to make the car move so intuitively you don't need to think too much about how you drive.

"We know if it's cold, if it's raining because the wipers are on, if you're on an incline, we can directly measure traction too. We measure steering angle, brake pressure, throttle.

"We take all this data and calculate 200 times per second what's happening and we can come up with a precise torque split [to maximise traction]."

CONCLUSION
Coleman professes that "the goal for AWD is to take the same dynamics for dry pavement and have it on slippery surfaces, or low-grip surfaces."

That may be true on a wet road, and it's fair to say the CX-5 was controllable on snow, but the front-end doesn't bite into corners like it does on dry asphalt.

Clearly there's still a long way to go in this respect, and perhaps it will take electric cars – with a motor in each wheel – and more advanced tyre technology to deliver dry-surface levels of grip on low-friction surfaces like ice and snow.

Of course, there's also the question of a level playing field, as there is with any comparison test against competitor vehicles staged by a car-maker, Mazda said all the cars were standard, but we – and Honda and Subaru – have no way of knowing for sure.

Nevertheless, one thing is certain. Mazda's part-time AWD system – as seen in the CX-3, CX-5 and, soon, the new CX-9 -- is remarkably effective and, at least in the conditions we tested it, showed its most direct rivals a very clean pair of heels.