2010 BMW X6 M: Fast and fun

Barreling around the racetrack, there’s little lean entering the corners, plenty of thrust on exit and a monster amount of grip everywhere, and if it feels taxed at all, it’s ever so briefly as the nose aims left and up from turn five for the steep climb out of the esses.

Road Atlanta is plain ol’ fast, and the BMW X6 M does well to keep pace, spilling gobs of power all over the track, blazing down the long back straight to nearly 140 mph, maneuvering like no two-and-half-ton pile of metal should. It’s exhilarating stuff, to be sure, only we’re left asking very many questions, and all of them are: Why?

Why would BMW make an all-wheel-drive M vehicle? Or an automatic M? Or an M ute at all?

Truth be told, the regular X6 makes little sense. It’s a sport-ute (regardless of BMW’s insistence on calling it a “sport activity vehicle”) with most of what makes the breed useful–that is, cargo hauling–lopped off in the name of coupelike styling while keeping the penalties intact, namely, a high center of gravity and

lots and lots of mass. Stuffing it full of 555 hp, offering a bevy of performance-enhancing electronics and slapping a big M badge on its sloping butt makes it a heckuva lot of fun, but it’s still a quirky vehicle with little compelling argument for its existence except that it’s, well, compelling.

And for some enthusiasts, that’s all that matters, which, we suppose, answers all those whys.

The magic for turning its 5,247 pounds into a road-going rocket is the specially tuned M engine, based largely on the 407-hp, twin-turbo 4.4-liter V8 found in the X6 xDrive 50i and the 750i. BMW swapped out the regular turbochargers on the base 4.4-liter for a pair of high-efficiency twin-scroll units, which themselves feed off a unique exhaust manifold that shuttles the outflow from paired but opposing cylinders to each scroll. This ensures a delivery of almost constant exhaust pressure to each turbo-charger, making throttle response almost immediate and turbo lag virtually undetectable.

source: autoweek