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DPC module integrated into the rear axle distributes torque between the rear wheels to improve handling stability.
Coupe or Crossover?
These days the genetic code for cars and SUVs is being mixed together at a rate that would make old Gregor Mendel's head spin. With all manner of crossovers already blurring the distinction between cars and utility vehicles to the point of incomprehensibility, BMW is about to announce yet another genetic mutation: the Sports Activity Coupe.
BMW has never been shy about inventing new vehicle categories out of thin air. (Don't think the X5 is a sport-utility vehicle; it's a sports activity vehicle!) So never mind that a coupe is generally defined as a closed car with two doors, while the X6 has four doors. The X6 has a coupelike fastback roof line, so that will have to be justification enough for calling it a sports activity coupe.
With its debut at the 2008 Detroit Auto Show, the 2009 BMW X6 takes what you thought you knew about crossovers and turns it on its head. And it's backed up by a twin-turbo, 400-horsepower 5.0-liter V8 and a twin-turbo, 300-hp 3.0-liter inline-6.
Gene Splicing
Given the specifications of the 2009 BMW X6, we're not going to hold semantics against the gene-splicers at BMW.
The X6 features the platform of the X5 and it has all the earmarks of a typical sport-utility, with all-wheel drive, massive tires and an interior package meant to haul both people and stuff.
But just like a BMW sedan, the X6 is brimming with a roster of steering, stopping and safety technologies. A short list of the BMW-signature engineering wonderment includes an adaptive all-wheel-drive system, sophisticated stability control, active steering and something new called Dynamic Performance Control that helps give this sport-utility a measure of carlike handling.
What BMW is trying to do here is bring us a sport-utility vehicle that handles like a car — a performance car. And that's a new thing.
Major Motivation
The BMW X6 comes in two flavors. The X6 xDrive50i packs a new twin-turbo 4.4-liter V8. Because the turbochargers are mounted in the vee between the cylinder banks, this engine can be packaged in the X5-derived chassis without reworking the front suspension. The X6 xDrive35i is powered by a 3.0-liter inline-6 that's essentially the same as that which comes under the hood of the 1, 3 and 5 Series.
Both engines combine turbocharging with direct injection, which is BMW's engine formula for the future. Relatively small-capacity turbos are quick to spool up, minimizing throttle lag. Direct injection affords a cooler intake charge, so the compression ratio can be higher to improve throttle response and fuel efficiency. Both engines feature BMW's variable intake timing on both the intake and exhaust valves to broaden the power band.
There's no arguing with the results, as both engines seem to offer an exceptionally broad spread of power. The V8 kicks out a dyno-sobering 450 pound-feet of torque from 1,800 rpm to 4,500 rpm, and the inline-6 holds its peak torque of 300 lb-ft all the way from 1,500 rpm to 5,000 rpm.
Likewise, each engine's peak horsepower is also delivered over a broad spectrum. The V8's peak output of 400 hp holds strong between 5,550 rpm and 6,400 rpm, while the inline-6 produces 300 hp between 5,800 rpm and 6,250 rpm.
BMW claims the X6 xDrive50i will get to 60 mph in 5.3 seconds thanks to all the V8 power, and then hit an electronically limited 155 mph when it's flat-out. The X6 xDrive35i is supposed to reach 60 mph in well under 7.0 seconds. Both engines have been paired with a six-speed automatic transmission that features shift paddles on the steering wheel.
X Marks the Spot
Like the BMW X3 and X5, the X6 has all-wheel drive as standard equipment. The fast-acting, electronically controlled multiple-plate clutch distributes power between the front and rear wheels, and the torque split is 40 percent front/60 percent rear in normal driving.
A new system also features a new technology BMW calls Dynamic Performance Control (DPC). The rear axle incorporates a differential that features its own planetary gearsets that are operated by electronically controlled multiplate clutches. It distributes power between the two rear wheels much like an active limited-slip differential.
When the X6 is carving through a corner, the DPC multiplies torque to the outside rear wheel, reducing understeer and helping the vehicle carve a tighter line. If the rear end threatens to lose grip in a corner, the DPC multiplies torque to the inner rear wheel and reduces oversteer. The DPC even works under deceleration, stabilizing the vehicle independently of engine load.
DPC is clearly meant to give the X6 a dimension of carlike high-performance handling on dry roads, but naturally it also works when the traction is slippery, so it enhances the X6's utility-style mobility when the road is muddy or even snowy.
This variant of the X5 platform has suspension tuning that's suited to its mission as a coupe. An array of sensors alter both the damping and the active antiroll bars, helping the X6 adapt both to terrain and your general level of driving enthusiasm. As a result, this utility vehicle can corner like a BMW, yet still maintain its composure over the bumps. Both the X6 xDrive50i and X6 xDrive35i are equipped with 19-inch run-flat tires, although 20-inch performance tires are optional for the V8 model.
Microchip Performance
Just about every electronic device at BMW's command makes an appearance in the X6.
There's all of BMW's safety stuff, including active cruise control, hill-descent control, hill-start control, trailer stability control, brake assist, brakeforce distribution, cornering brake control and even more stuff with the brakes we don't have space to mention. Thanks to the DPC unit, BMW's stability control has been calibrated for a higher threshold before it kicks in, so the X6 offers a greater scope for enthusiasm behind the wheel than you'd expect from a sport-utility.
But wait, there's more! There's optional active steering to deliver a quicker ratio during low-speed maneuvers. The X6 also has dynamic traction control, so you can dial in a setting that will permit more wheelspin for some old-school, tire-burnin' fun!
It all works together with the X6's integrated chassis management, so this is one vehicle that's trying to optimize itself for the road ahead at every second.
Mostly Sport, but With Some Utility
Though the 2009 BMW X6 is far from a family hauler, its interior is designed to carry four passengers in comfort. Despite the fastback roof line, the rear seats offer headroom that's only 1.1 inches less than you'll find in the second row of an X5. An available rear-seat entertainment system and a rear center console also make backseat life more luxurious.
If you're hauling stuff instead of people, the optional power rear hatch affords access to 25.6 cubic feet of cargo volume, and there's plenty more once you flip down the 60/40-split second-row seat.
As to whether this utility is really a carlike coupe is probably a matter for another time, but there's no question that the combination of a big (though troubled) styling statement and a high-performance personality sets the X6 apart from the usual suspects in the sport-utility category.
No word yet on pricing, but we know the X6 will be at a BMW dealer near you as the spring ends. There's nothing like it, and so far this seems like a good thing.
First Look: 2009 BMW X6 xDrive50i
Delicious styling, interior, and engines. A sure winner for BMW. I can't wait to see it in person this Saturday!
M
I thought the new V8 turbo was based on a 4.8 liter engine 
