BMW M6 GranCoupe 2013 Review - International

Except BMW has gone further than Benz, which merely created both conservative and slinky machines off the same underpinnings, then gave them to AMG to fiddle. BMW has taken the 5 Series and created an entirely new three-model 6 Series family, and then it gave all three of them to M.

Now, M, sitting around patting itself on the back for another M5 well done, didn’t need long to create the M6 Gran Coupe, largely because it more or less changed the panels across to the new body and filled the cabin full of M6 Coupe.

The M6 Gran Coupe carries the M5’s wheelbase, its engine, transmission, suspension, cooling system, brakes and electronics and chassis. And it carries the M6 Coupe’s dashboard, seats and trim design.

But, BMW insists, the M5 customer is not the same one as the M6 Gran Coupe customer. A part of that is that the M5’s body fits in with a relative lack of pretention wherever it goes (and the M6 Gran Coupe might not) and part of that is that the M6 Gran Coupe is even more luxurious and comfortable where the M5 is meant to be slightly more athletic.

Both cars hit 100km/h in 4.2 seconds. Both cars are limited to 250km/h (in ultra low-speed Australia, anyway). Both cars are tremendously fast in their in-gear acceleration and both cars post 9.9L/100km average fuel consumption in Europe.

Every BMW official at the M6 Gran Coupe launch used the word “luxury” well before the word “power”.

That’s partly because BMW is positioning it above the M5 at a sniff beneath $300,000 and partly because it actually is luxurious.

Its driver’s seat is a particularly pleasant place to be, with the long, curving strip of leather-clad dashboard joining the centre console to create the driver-focused interior that the M5 lacks. There are beautiful touches of trimming throughout, including a leather strip that runs the length of the roof lining.

That strip is there, flanked by Alcantara, largely to remind the driver that he or she’s also paid for a carbon-fibre roof and the strip’s shape runs the line of the longitudinal aero groove in the roof’s centre. Yes, it saves weight, but it’s also meant to hark back to the old M3 CSL, even though this car weighs 1875kg before its tank gets filled.

In a dash so sculpted, it looks a little like an afterthought trimmed in fake, metal-look plastic, but it’s very big and it’s easy to read in any light.

BMW’s design boss, Harim Kabib, admits it’s not a perfect solution but points out that a pop-up screen this size would demand a much larger dashboard that would encroach heavily on the cabin and front legroom in particular.

There is a very large boot beautifully trimmed in leather, more than reasonable rear legroom and a pair of terrifically supported, heated leather seats up front.

With a wheelbase 113mm longer than the M6 Coupe’s, you’d be right to expect more rear legroom, but getting into the back seat can sometimes be just as tricky as the two-door. The lower roof line means even mid-sized people will have to duck to get in and out of it, while the shape of the frameless windows on the rear door means it protrudes a long way behind the rear door-handle and can smack you in the ribs if you’re not careful.

With a 460-litre boot, its luggage area is roughly on par with the CLS 63’s, but will be considerably smaller than the upcoming RS7’s and it also suffers from a high loading lip, largely because the boot sill hides a large strengthening brace across the back of the car.

MECHANICAL

The 4.4-litre V8 has its pair of twin-scroll turbochargers snuggled inside the engine’s vee and uses both variable valve timing and variable valve lift, along with direct fuel-injection.

This helps it to crank out 680Nm of torque from just 1500rpm and it holds that figure until 5750rpm. By then, the 412kW power peak is all primed to take over the headlines, and it does that happily from 6000rpm to 7000rpm. But it does it only on 98 RON fuel.

The newest M6 runs all of that power through a seven-speed dual-clutch automated manual transmission to its 20-inch rear wheels, which are wrapped in 265/35 R20 rubber up front and 295/30 R20 boots at the back.

Part of the reason it needs that much power is that it’s not particularly light, with 1875kg spread 50:50 between the front and rear axles. That weight is also part of the reason it uses 14L/100km around town and 7.5L/100km out on the highway, so you’ll need to fill its 80-litre tank with some frequency.

COMPETITORS

First there was the upgraded E 63 AMG in both rear- and (for left-hook markets, anyway) all-wheel drive guise and they are precursors to the sleeker looking CLS 63 facelift that is nearing the end of the development pipeline.

Last week came the twin-turbo V8-powered RS 6 wagon from Audi’s quattro division and that forms the basis of the upcoming RS 7 Sportback, which will be even faster.

And now there’s the M6 Gran Coupe from BMW, which will join the M5 in defending BMW’s sports sedan pedestal. Well, it would except that BMW insists it’s a coupe, even with its four doors.

The trouble with the M twins’ defensive position is that where they both post 0-100km/h times of 4.2 seconds, the Audi RS 6 is a 3.9-second proposition, the RS 7 will be a tenth quicker than that and the sharpest of the E 63 AMG brutes is a 3.6-second device.

A tenth here and there can be forgiven, but when the gap to 100km/h blows out to more than half a second, it’s starting to be a problem.

The odd thing is that the AMGs, M and quattros are all within a scattered handful of horsepower of each other and the obvious point off the line is that the RS models and the fastest AMG E 63 are all-wheel drive. And all of that ignores the strength of Porsche’s Panamera Turbo…

There is much to think about, then, if you like fast German V8 sedans stuffed full of leather.

ON THE ROAD

The real reason for its (relatively) tardy getaway seems like it loses the three-way battle between its computer brain, the longitudinal capacity of its rubber and the brawn of its engine, which combine to rob it of most of those tenths before it even hits 50km/h.

Beyond that, not much other than mid-engined supercars are pulling away from the M6 Gran Coupe and it’s more likely to be reeling some of its opponents back in by the time it’s reaching beyond 150km/h. Not that we would do that in Australia.

There is such a charm and breadth to its character that you don’t worry about the data shortfall for very long. It feels so much more versatile than the M5 that you start to think that maybe BMW’s marketers were on to something by insisting the two weren’t competitors.

It is capable of using its Comfort setting to roll softly through the most awful roads at very low speeds while cosseting its occupants in much the same way as a 7 Series. For one reason or another, the M5 isn’t as capable of this.

It’s also capable of tightening up its suspension, throttle response and steering and, at the same time, loosening the muzzle of its skid-control system as well as offering three stages of gearshift aggression. It’s admirably crisp in its fastest setting and genuinely comfortable in its softest.

There may well be a big set of low-profile boots keeping the rims off the ground, but there’s little of the noise typical of this type of thing.

The wrap-around console makes you believe that the car is there for you and you alone, and so does the powertrain, which works very hard to make anything in front of you get big in a hurry.

The engine is brutally strong from very low rpm and sings happily to high rpm. Its mid-range strength is a highlight. Left in a high gear, a full-throttle boot makes the V8 bellow deeply in its labours to saturate the cabin in a ludicrously rich sound that never sounds anything like as artificial as it actually is.

The raw engine note would be enough on its own, but the synthesised note is something else again and by the time you’ve thrown in all of its pops, burbles and wooffles on the overrun and on each downshifts (in Sport mode), it’s an overwhelmingly warm aural package.

The chassis might be technically the same as the M5’s but it doesn’t feel the same. Like its sibling, it never feels nimble exactly, but it never feels completely stolid, either, and what it really brings to the party is stubborn high-speed stability.

That’s no bad thing because no matter how vociferously BMW denies it, this is designed for high-speed work on German autobahns first and foremost. Our M6 Gran Coupe ran the higher 305km/h limit that the Australian M6 Gran Coupes won’t get and the car hit it, hard and quickly.

Its ability to fling the tacho needle into the redline, even in fifth or sixth gear, is astonishing and it keeps slicing through the air with a rate of acceleration that suggests certain rules of air resistance don’t apply to it.

Even more impressive than the sheer speed at high revs was that the body and the chassis sat there, unshakably stable, even when we needed a full ABS stop to avoid an errant Golf.

The four-door M6 is not only fast and stable, but it’s ridiculously comfortable at low speed, too. There are times when the exhaust note can drone on a bit at constant speeds (unfortunately, 80km/h and 100km/h were amongst them), but it makes up for it with a level of ride comfort it just shouldn’t be capable of.

Big, fast, luxurious German V8 sedans are where it’s at right now and while the M6 Gran Coupe trails its foes to 100km/h, it’s right on the money everywhere else.

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