BMW M6 Gran Coupé

Effortless speed is a given, but true M-cars need more than that

The last Gran Coupé I drove, the 640d, was a BMW that just worked. Effortlessly powerful, comfortable, frugal, quiet and blessed with a massive range, I wondered at the time how well a car over five metres in length would respond to the ‘M’ treatment. Being frank, it didn’t feel an exactly natural candidate. Then again neither did the X5 or X6 SUV and that didn’t stop BMW slathering Motorsports badging all over them.

The hottest version of BMW’s Mercedes CLS-apeing stretched four-door 6-series comes with a 552bhp, twin turbo V8 under its lengthy bonnet. It’s so fast that 20 years ago that level of performance would have been available only from a highly specialised, vastly expensive hypercar like a Jaguar XJ220. Now it is entirely routine, wrapped up in a shape that will carry five at a distinct pinch for whoever is in the middle of the back row and delivered with almost insouciant ease.

I don’t usually have much time for those who claim not to realise how fast they’re travelling, but it’s easy to underestimate the speed of this M6 by 10 or even 20mph if you find enough open road to let it settle into what feels like a natural cruise.

And the fact that it still doesn’t feel like an M-car to me probably says more about this writer than the car he’s driving. Somewhere deep in my programming there’s a line or two of data that says a proper M-car has to be quite light, have two doors, power from a small capacity, naturally aspirated engine capable of spinning at scintillating speeds and prioritise driving pleasure above all other considerations. But that’s not what M-cars are today. Today an M-car is simply a high performance BMW, be it a coupé, saloon, SUV or crossover like this.

It’s true, too, that the moment I stopped snorting about its badges and concentrated more on the car to which they were attached, I started to like it a whole lot more. It is a superb means of crossing vast distances at great speed, in considerable comfort and some style.

But any more so than that 640d? Certainly not. The M6 may be a little more fun to drive, but that’s irrelevant when you consider the cheapest M-car, the M135i, costs a third of the M6’s money and is far more fun. In the real world the 640d would be scarcely slower and, over a long distance, would prove hugely faster because BMW says it will return more than 50mpg. Using the same calculations, the M6 can’t get near 30mpg.

One more thing. At £97,515 the M6 begs the question why, if you were in the market for such a car, you’d not plump for the similarly fast and powerful but neater and £15,000 cheaper Mercedes-Benz CLS63 AMG? Reasonably good though this M6 is, it’s not that good.

Factfile

Price: £97,515
Engine: 4.4-litres, 8 cylinders
Power: 552bhp @6000rpm
Torque: 502lb ft @1500-5750rpm
Transmission: seven-speed twin-clutch Drivelogic
0-62mph: 4.2sec
Top speed: 155mph
Economy: 28.5mpg
CO2: 232g/km