While filling up the admittedly thirsty 2015 BMW Alpina B6 at my local gas station, an elderly gentleman pulled up in an old Fusion and eyed the blue specimen.

“They still make Alpinas?”

Turns out he had been a car enthusiast in his younger years, having owned a Jag, a Porsche and an Aston Martin. He knew Alpina from its successful racing partnership with BMW, when the motorsport duo won three European Touring Car Championships in the seventies.

Indeed, there is some history behind the Alpina badge. It all started in 1962 when Alpina founder Burkard Bovensiepen turned up the heat on a BMW 1500 by slapping on a pair of dual-choke Webber carbs. In the years following, legendary racers such as Hans Stuck Jr and Niki Lauda piloted Alpina BMWs to victory.

In 1988 Alpina said goodbye to motor racing and concentrated on the business of building their special brand of BMW road cars – fast, luxurious and oh-so exclusive.

And so to this 2015 B6, which is Alpina’s take on the BMW 6 Series Gran Coupe. Ringing in at $150,000, give or take, this rare beauty is a study in subtle aggression. And it sure doesn’t hurt that BMW’s Gran Coupe is surely one of the prettiest cars on the road today. A few body mods, Alpina Blue Metallic paint and 20-spoke 20-inch alloys have it dressed to kill.

So why would anyone want this car when BMW already sells three variants of the 6 Gran Coupe?  Drop into your local BMW store and you’ll find the 315-hp six-cylinder 640i xDrive at $87,900, the 445-hp 4.4L V8 650i xDrive at $99,800, and the full-bore rear-drive M6 that starts at $127,900 and extracts an extreme 560 hp from the same 4.4L V8.

Well, you have to drive it to find out. After a week in the B6, I totally get the appeal of this exclusive 540-hp grand tourer. One’s initial assessment might be, “It’s just an M6 with all-wheel drive.” Ah, but it goes deeper than that.

The Alpina recipe leans more on the side of luxury than on-track performance, but having said that, the B6 is hardly a poseur. Those body bits are functioning aerodynamic aids as this four-door coupe posts the highest top speed of any BMW – thanks to its Michelin Pilot Super Sport tires and the deletion of that pesky 250 km/h governor found on all other high-po Bimmers. Oh, and let’s not forget the Alpina-modified 4.4L twin-turbo V8 that makes 540 hp (down 20 hp from the M6) but a robust 540 lb-ft that trumps the M6 by 38. Give it enough room and the Alpina B6 will see 318 km/h.

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