 2013 Acura RDX Tech. Click image to enlarge |
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Review and photos by Chris Chase
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2013 Acura RDX
Just as it seems every other auto manufacturer is flocking to the turbocharged four-cylinder as a fuel-efficient replacement for the ubiquitous V6, Acura moves the other way with its second-generation RDX crossover. Where the original had a 2.3L turbo motor, its more grown-up replacement becomes part of the flock of Hondas and Acuras using the company’s 3.5L V6. It arrives in the RDX just as numerous other crossovers – the BMW X3 and Hyundai Santa Fe, notably – adopt turbocharging.
The argument that a smaller, turbocharged engine will run more efficiently than a larger V6 producing similar horsepower does hold some water. I’d suggest that in many types of vehicles, crossovers included, most buyers couldn’t care less what’s under the hood, as long as the car goes the way the target buyer thinks it should, and isn’t a gas hog.
If fuel consumption is a concern, Natural Resources Canada’s estimates for the new RDX paint a positive picture, with ratings of 10.7 L/100 km (city) and 7.3 L/100 km (highway). Those figures are an improvement over the outgoing RDX’s, but don’t break any ground in this vehicle class.
Real-world driving tells the true story, however. My RDX tester averaged 12.6 L/100 km in city driving, and pulled off 8.5 L/100 km on a road trip that took us along Ontario’s Highways 416 and 401 at cruising speeds between 110 and 120 km/h. A four-cylinder BMW X1 I tested last year averaged 10.1 L/100 km in city driving, and a Ford Escape with that company’s 1.6L turbo (and much less powerful) engine averaged 10.9 L/100 km in the city. I haven’t yet had the chance to do a full road test of the new Santa Fe.
 2013 Acura RDX Tech. Click image to enlarge |
Given the way the market is moving toward turbocharged engines with direct fuel injection, Acura’s decision to stick a V6 in the RDX seems based on economics. It saves the company the cost of developing a new turbocharged engine (the old RDX’s engine was the only one in the Honda/Acura fleet that used turbocharging), but still gives the company some fuel-saving tech to talk about.
This engine has Honda’s Variable Cylinder Management (VCM) system, which shuts down three of the engine’s six cylinders under light loads – when maintaining a constant speed or accelerating very gently on flat roads. It works well, insomuch as you can actually tell from inside the car. When VCM is active, the sensation is a bit like that of “lugging” an engine at low revs, in too high a gear. A very subtle vibration can be felt through the car’s structure, but you have to pay attention to notice.
Any kind of meaningful acceleration requires bringing those three lazy cylinders back to life, which happens just as imperceptibly. Throttle response is very good, without being abrupt, and the also-new six-speed automatic transmission is great at doing what it needs to do, when it needs to be done. Manual control happens via shift paddles behind the steering wheel. These work all the time, but in regular drive mode, the transmission reverts to full automatic operation after a few seconds, unless you’ve downshifted for engine braking, at which point it will hold whatever gear you’ve selected until the car stops or the driver gets back on the gas. A “sport” mode calls up a more aggressive shift program that also allows full manual control.
