2010 BMW X6 M
Last Updated on Saturday, 06 February 2010 14:52 Written by Christopher Ihara Saturday, 12 December 2009 18:36
First Drives
| Article Index |
|---|
| 2010 BMW X6 M |
| Page 2 |
| All Pages |
Magazines throughout the history of the automobile have sung praises to BMW’s rolling engineering marvels. Uncompromising performance, technological innovation, and the driving soul that is unique to BMW, is painstakingly crafted into each of their cars. Not only has BMW mastered the infusion of these elements into their traditional product line, but they were one of the original pioneers of the factory “tuner” car with the development of their “M” series cars.
But is it possible to take the essence of what makes a car an M and apply it to their Sports Activity Vehicle (SAV) line? In the heart of South Carolina, American workers will assemble just such a vehicle: the BMW X6 M.
While the current BMW X6 is certainly no slouch in its market segment, the new X6 M aims squarely for the jugular of the Porsche Cayenne Turbo. Refinements at every corner of the X6 fill it with the essence of what an M badged car is supposed to be. In addition to the suspension, brake, electronics, transmission and wheel changes BMW has created one of the most innovative twin turbo systems on the planet - combine these ingredients and you have a recipe for a seriously fast SAV.
Under the hood of the new BMW X6 M lies a twin-turbo 4.4 liter V-8. On paper the use of twin turbos seems like old news until you actually see the engine. BMW engineers swapped the traditional placement of the exhaust manifolds from the outboard sides of the cylinder heads to the inboard sides. This means that the twin turbos reside in the middle of the engine’s “V” configuration. But this is more than simply swapping the aluminum heads to opposite sides of the block.
 2010 BMW X6 M Twin Turbo Configuration |
|
|
Each turbo is fed by two sets of tubular headers that join pairs of cylinders together and crisscross the engine’s valley. By combining the exhaust of each cylinder to the next in the firing order sequence it is possible to create a constant flow of burnt gasses to spin the turbos. The entire package is wrapped with a heat shield to keep from cooking the aluminum engine block and heads.
Once compressed to over 21psi (1.5 bar), a pair of liquid to air intercoolers chills the air, before going through composite intake manifolds located on the outboard side of the heads. Electric pumps move water from the intercoolers to heat exchangers located on each side of the X6 M’s gaping front openings. There fresh air cools the fluid before it is returned back to the intercoolers.
The end result is simply staggering. The X6 M’s 4.4 liter, 32 valve Direct Injection, twin-turbo V8 makes peak torque of 501 lb-ft from 1,500 to 5,650 RPM, which creates a torque curve on the dyno graph that looks like a picture of the Utah Salt Flats. Horsepower rockets upwards as RPMs climb to a peak of 555 BHP @ 6,000 RPM.
Besides the layout of the turbos, the other unusual characteristic of the BMW X6 M’s engine is its sound. Missing is the traditional 4th order V8 sound which is instead replaced by an exotic throaty growl reminiscent of a V12 or V6. Up and downshifts in manual shift mode cause the engine’s computer to cut out ignition and fuel to obtain maximum shift speeds. These cutouts create a distinctively unique burble in the exhaust note every time the gears change.
