It’s Alpina’s 600bhp B6 Gran Coupe

This is the fastest accelerating BMW Alpina model ever built. It is the BMW Alpina B6 xDrive Gran Coupe, and alongside that whopping great name, it has a whopping great engine.

Long time BMW tuner Alpina has taken the company's mighty 4.4-litre twin-turbo V8, and increased the unit's power from 560bhp to a cool, clean 600bhp and 590lb ft of torque in this B6.

How? Two specially-built, larger-diameter turbochargers replace the standard ones, together with a high-performance water-air intercooler system, a larger volume low-temp heat exchanger, additional intercoolers, and some "optimization" of the intake ducting and air filter housing.

Then there are new Mahle pistons designed to deal with more boost - up to 1.2 bar (17.4 psi) - and a 10:1 compression ratio to top it all off.

All this is coupled to a ZF eight-speed auto gearbox (not a dual clutcher) with Alpina specific software, BMW's xDrive four-wheel-drive system, stiffer springs, Alpina-specific damping calibration, increased front wheel camber, and even high speed tyres.

It'll go from 0-60mph in 3.6 seconds, and top out at 200mph, which measures up well against BMW's own rear-drive M6 Gran Coupe (0-62mph in 4.2, limited top speed of 155mph); a car don't forget, the TG telly boys recently took to Australia.

You'll notice the classic 20in Alpina wheels (with monster brakes underneath), a new front spoiler, splitter and air channels, rear spoiler and twin-tailpipes. Inside there's more leather, blue instrumentation, and many options.

No prices have been announced, and it'll go into limited production, but we suspect you'll pay upwards of £100k, at the very least. Would you rather have an M6 GC, or this Alpina B6 GC? Remember, Alpina has form in retooling BMWs - the B3 Bi-turbo we drove a while back was a cracker...