German for "Why?" The 2010 BMW X6 M

It sounds like the world’s largest sportbike; an exercise in mimicry from the reverse-flow turbocharged V8. With the familiar lights of the George Massey tunnel flashing across the sculpted hood at an impossible pace as the blood red BMW surges forward, surfing a wave of auditory ferocity. And all of the sudden it stops. At 6,000 rpm, there is a millisecond’s pause. The revolutions plummet. The unrelenting pressure on your chest releases as your breath catches in your throat. And suddenly the monster under your right foot erupts anew; the explosive expulsion of exhaust gases easily overriding the sound of the twin-turbochargers gulping in new, fresh air. This is the 2010 BMW X6 M.

And at the heart of it all is this: a 555 horsepower, twin-turbocharged V8. The most powerful ever fitted to a sport utility/activity vehicle, words cannot express this engine’s character. With a power output that’s closer to Ferrari’s new 458 Italia than Porsche’s Cayenne Turbo and more torque than a Hino commercial truck, it produces some very impressive numbers. But those numbers are only half of the equation. Although based on the same V8 found beneath the bonnet of the standard issue X6, the M variant replaces the turbos with a pair of twin-scroll units nestled between the cylinder banks. Although it may seem unorthodox, this reverse-flow layout allows BMW to mount the turbochargers on a siamesed exhaust manifold, essentially doubling the number of exhaust pulses available to each turbocharger. Negating turbo lag, the new exhaust manifold also endows the X6 M with a uniquely sonorous exhaust note that’s more akin to BMW’s two-wheeled products than any of their quadripedal efforts. And if you need more of it, depressing the M button will open up a pair of baffles in the exhaust, almost doubling the V8’s volume.

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But sadly, no amount of amplification will allow that intriguing exhaust note to penetrate the cabin. Of proud Germanic design, the X6 M’s interior pairs penthouse levels of comfort with bunker-like levels of solidarity. Almost identical to the X5’s cabin in design, the X6 M boasts such luxury features as powered doors (you need only latch them slightly; motors will pull them inward to close fully), a power liftgate, a heated steering wheel, heated seats, iDrive, a huge sunroof and just about every other trinket you can imagine. And although fitted with noisy snow tires, the X6 M’s sound tuning is exceptional, allowing only a hint of the cacophony outside to filter in.

But all that luxury equipment has a price tag, and it’s a heavy one at 5,265 pounds. To put that figure in perspective, the X6 M could play teeter-totter with the average white rhinoceros; itself the world’s second largest animal by weight. However, while that weight may seem to saddle the suspension with an impossible task, a quick jaunt down any twisting road will have you convinced of the merits of static downforce. Equipped with a performance-tuned version of BMW’s xDrive all-wheel-drive, the X6 M shuttles power from front to rear as needed, while the Dynamic Performance Control channels power across the rear axle through corners to bring the X6 M’s yaw rate in line with the intended path to be travelled as determined by the steering angle sensor. Throughout all this, the familiar DSC system secures traction to varying degrees depending on the mode selected. And while the actual hardware underpinning all this electronic wizardry may offer no surprises, the dampers are electronically adjustable and the roll bars actively adjust themselves to compensate for lateral loads.

And it all works exceptionally well. Bend the X6M into a corner with some aggression, and the hulking SUV/SAV seems to slough off the building cornering forces without breaking a sweat. Dial the various electronic settings to their sportiest available options and the X6M rewards with a freight train-like ability to barrel through sweeping corners as if on rails. Although relatively tall with plenty of airspace under the differentials, there’s absolutely no body roll, and upsetting it’s electronically imposed neutral cornering attitude takes a conscious effort. That said, there’s simply no way to make this amount of girth change direction all that quickly, and the X6M proves less than agile as a result.

But even with its seemingly bottomless reserves of capability, there’s no getting around the three letter elephant in the room: why? The X6 is already an enigmatic vehicle, and the addition of 555 horsepower doesn’t make its existence any easier to justify. In fact, its ability to inhale hundreds of kilometres in a single bounding leap just messes with your mind even more. As drivers, we’re used to compromising. Blistering performance must be offset by spartan acoutrements and an inability to crest even the slightest snow drift. Conversely, all-road capability must be offset by a too-tall stance and a tippy attitude. The X6 M is to these compromises as an atom bomb is to the Bikini Atoll; it combines the performance of a sports car with the all-road prowess of an SUV, all the while delivering the comfort levels of a first-rate luxury saloon. Does is give up a little ground to the various vehicles occupying the extreme ends of these individual spectrums? Yes, of course. But when that twin-turbocharged V8 does its best impression of the four horsemen of the apocalypse between second and third gears, nothing else will matter.