Road & Track road test of the RDX

[WashUJon]

The RDX could just as well have been named “Enigma,” because its place in the automotive world is a puzzlement not seen since Yul Brynner ruled siam. It’ll sprint nearly neck-and-neck with a Volkswagen GTI through the quarter mile; they both clock in at 14.8 seconds, though the GTI has a higher trap speed. It’ll outskidpad and out-slalom its own sportssedan stablemate, the Acura TSX. and while rock-hopping on the Rubicon Trail is beyond its capabilities, the all-wheeldrive RDX has sufficient ground clearance and ramp angles to tackle a deeply rutted fire road. Its interior? Luxurious, downright sporty and brimming with the latest technology, seemingly at odds with its scrappy-looking sheet metal.

Yes, the RDX defies easy classification, but it’s a fun way to scoot around town, and much of that is attributable to its turbocharged powerplant, a 2.3-liter inline-4 based on a strengthened version of the TSX’s cast-iron-sleeved die-cast aluminum block. The turbo uses a variable-flow system with an electronically controlled, vacuum-actuated flap that channels highvelocity exhaust gases at the turbine for quick low-end response; the flap opens fully as revs increase to maintain optimum gas flow, up to a peak of 13.5 psi. The turbo’s charge is chilled by an intercooler atop the engine that’s fed ram air from a generous inlet above the grille. The result is a solid 240 bhp at 6000 rpm and 260 lb.-ft. of torque at 4500.

Channeled through a 5-speed sequential sportshift automatic, this output punts the RDX off the line with authority, especially when the sport mode sharpens the shift feel. There are steering-wheelmounted paddles for sequential shifting, and the transmission’s console-mounted selector need not be in sport mode for them to function. on throttle tip-in, there’s just a moment of lag, then a strong, linear surge of acceleration that might make you think that a) there’s more than 2.3 liters at work here, or b) the curb weight is less than the portly 3940 lb. We measured, because 60 mph can be reached in just 6.3 sec. Small throttle openings at low speeds generate a muffl ed hiss from the turbo — not objectionable, and just enough to let you know that the system is spooled up and ready to deliver.


Upping the fun quotient is a chassis that handles better than it ought to. The RDX is based on Honda’s global light truck platform that’s shared with the new honda CR-V. It has MacPherson struts in front, a multilink setup in back and a Michelin P235/55R-18 all-season tire at each corner. More interestingly, the RDX has a slightly simplified version of the flagship Rl sedan’s super handling all-Wheel drive (SH-AWD), a full-time system that not only apportions torque front to rear, but also to the left and right rear wheels. up to 70 percent of drive torque can be sent to the rear wheels when both cornering and accelerating. And up to 100 percent of that torque can be sent to either side via dual electromagnetic clutch packs as conditions dictate, based on available engine torque, input from accelerometers, and sensors for steering angle, throttle position and wheelspin.


The result is a steering effect from the rear, not unlike the way a tank is steered with the differential speeds of its right and left tracks. It does reduce understeer somewhat, but the truth is that you have to drive the RDX pretty hard to realize any benefit. The effect is noticeable when charging through a freeway cloverleaf, or when accelerating hard and making a tight 90-degree turn, pulling out of a driveway for instance. It feels as if the yaw axis is moved roughly from the dashboard to directly beneath your seat, and imparts a tidy and precise feel to cornering. Kind of cool, but are the benefits worth the extra weight, cost and complexity? Hard to say.

No such quandary exists inside, where supportive leather-trimmed seats and big gauges, set in round hooded pods with crisp backlit LEd illumination, speak to the RDX’s driver-oriented nature. There’s a nice variety of shapes and cross-hatched/ grained textures, with a prominent silver-color slat breaking up the dash horizontally. Even the shift-selector knob gets special mention, as it fits perfectly in your palm. Storage is plentiful, the most impressive area being a center console compartment that can easily conceal a briefcase or laptop computer. In the rear cargo area, there’s a reversible floor panel — hard plastic on one side, carpet on the other — that can also serve as a partition to create an enclosed “trunk.” The 60/40 rear seat folds flat, a two-step process where the lower cushions flip forward, followed by the seatbacks. People space is generous too, with lots of elbow, shoulder and head room for all occupants; though 6-footers in the rear seats may be tight on knee space, they’ll find commendable head room. Our test RDX had the optional Technology Package, worth its weight in gold-plated pocket protectors. Although it’s a $3500 hit, the package includes a navigation system with real-time traffic data (freeways are color-coded to represent the average speed of traffic flow), a hands-free phone that links with your cellphone via Bluetooth technology, a rearview back-up camera, and a premium 410-watt sound system that can play CDs and DVD audio discs. There’s also voice control that recognizes more than 650 command phrases and 1.7 million city and street names, making it possible to program the nav system by voice only. as is fashionable, a tilt-and-twist controller sprouts from high on the center stack, useful for programming the nav system the old-fashioned way and/or calling up major audio system and climate control functions. It seems that among the steering-wheelmounted switches, the controller widget, voice commands and dedicated hard buttons, there are roughly five different ways to accomplish any one thing!


In all, the RDX is an impressive ball of technology, function and performance. (That performance, by the way, comes at a fuelmileage price — our best two tankfuls of admittedly brisk urban driving didn’t crack 14 mpg, though Acura’s estimates are 19/24 mpg, city/highway). Will people flock to Acura showrooms to buy it, or is the RDX the answer to a question no one asked? We think it has more than a fighting chance.

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