Sky’s the LIMIT Skyactiv technology keeps Mazda CX-5 fit at high altitude
SALT LAKE CITY, Utah — It was surprising how comparatively little horsepower the 2014 Mazda CX-5 lost traipsing around Utah’s mountainous peaks like a four-wheeled billy goat.
Altitude, as anyone who’s ever driven over any mountain range can attest, saps power. The air — as my straining lungs reminded me — becomes less dense the higher up the trail you go. This decreased density means each cylinder gets less air to compress and the engine has to compensate by injecting less fuel into the combustion chamber.
The end result is each of the “bangs” that make up an internal combustion engine’s motive force is a little less robust than it would be were the engine breathing closer to sea level.
The standard solution for internal combustion’s altitude sickness has always been turbocharging. Turbos force-feed air to an engine and are able to overcome mountain-high oxygen deprivation.
It’s a tactic that worked for aviation piston engines back when jets were just a gleam in Hans von Ohain’s eye and it works just as well for automobiles climbing toward cloud-covered summits.
Unfortunately, the CX-5, unlike many of new compact cars and sport utes hitting the market, is not turbocharged, Mazda taking a solitary road toward greater fuel economy that includes (so far) neither turbocharging nor hybridization. And yet, the CX-5 acquitted itself somewhat better than the CX-9 that accompanied it up the mid-western ski slopes.
Indeed, while the CX-9’s 3.7-litre V6 felt like it lost the anticipated 30 to 40 per cent of power from the altitude (that peaked at well over 3,500 metres), the CX-5 seemed to only lose perhaps 20 per cent.
Why? Perhaps it’s the miracle of Skyactiv. Mazda’s trademark “revolution” in internal combustion claims all manner of technological enhancements, but the one that constantly catches my eye is the stratospherically high 13.0:1 compression ratio.
For those unfamiliar with internal combustion terminology, that’s a measure of how much air is compressed inside a cylinder before the explosion that is internal combustion is ignited. The more the air is squeezed, the greater the resultant explosion and 13.0:1 is usually the kind of tuning reserved for racing cars and the high, naked ovals of NASCAR.
Seemingly, it also helps the CX-5’s new 2.5L four-cylinder engine overcome altitude sickness.
Of course, prancing about like a mountain goat was not Mazda’s mandate for Skyactiv technology, but rather good old-fashioned performance fuel economy. On the first front, the new 2.5L Skyactiv four-cylinder is largely successful because it is significantly more powerful — 29 horsepower and 36 pound-feet — than the 2.0L four that still powers the base CX-5 GX ($22,995).
Its maximum 184 horsepower may not quite match the more than 200 horsepower of some of the 2.0L turbocharged sport cutes — Audi’s Q5 and the BMW X1 come to mind — but it’s more than powerful enough and easily the match of Toyota’s new RAV4 and Honda’s CR-V.
More importantly, it easily bests those turbocharged competitors when it comes to real-world fuel economy. Oh, Natural Resource Canada’s official fuel-economy ratings are only marginally better for the CX-5 — 8.5 litres per 100 kilometres in the city and 6.6 L/100 km on the open road versus the BMW’s 9.1 and 6.2 L/100 km — but the Skyactiv technology really shines on the road. Despite significant time spent rollicking about off-road trails — usually a killer of fuel economy — our CX-S GT averaged less than 9.0 L/100 km, stellar numbers considering the conditions.
Likewise, for something not pretending to be a Land Rover, the CX-5 acquitted itself quite well off-road. No, it doesn’t have the wheel articulation of an LR4 or the locking differentials of a Defender, but our traipse across the Cottonwood Pass did not overly challenge the little Mazda. Considering the wilderness we covered, I suspect few will need more off-road ability than the CX.
Most of the rest of the Mazda remains the same for 2014. Besides the engine upgrade in the $28,650 GS and $33,250 GT, there’s a new Smart City Brake Support (SCBS) system available, which will automatically brake the CX-5 to a standstill if it detects an imminent collision.
Otherwise, the CX-5 remains unchanged for 2014. It remains a sporty handling, fairly roomy and a decidedly pretty compact sport ute. It offers superior performance to its direct competitors and, compared with the turbocharged fours that rule the compact premium segment, better fuel economy.
Many lamented Mazda’s decision to stop producing its CX-7. The new CX-5 is a more than worthy replacement.
The new Mazda CX-5 is a sporty handling, fairly roomy and a decidedly pretty compact sport ute.
A well-equipped 2014 Mazda CX-5 can be purchased for under $30,000.