Detroit show: BMW M6 Gran Coupe outed

BMW has revealed its fastest four-door autobahn burner, the M6 Gran Coupe.

The slope-backed, coupe-style sedan will appear in the flesh at the Detroit motor show on January 14, and will complete the BMW M6 trifecta when it lands in Australia in the third quarter of 2013 to join the two-door M6 Coupe and Convertible that arrived here last month.

Australia’s first deliveries are scheduled for March production, probably arriving in Australia mid year for a July or August showroom debut.

Although pricing will not be revealed until closer to launch, BMW Australia expects the M6 Gran Coupe to slot between the $292,500 M6 Coupe and $308,500 M6 Convertible.

The twin-turbo 4.4-litre V8 Gran Coupe can scurry from zero to 100km/h in the same 4.2 seconds as the M6 Coupe, making it one tenth faster than the existing swiftest BMW sedan, the M5 (4.3 seconds).

It is also two-tenths of a second quicker in the sprint than the car than many will consider its closest rival, the Mercedes-Benz CLS 63 AMG (4.4 seconds), although not as quick as the considerably more expensive Porsche Panamera Turbo (3.9).

The M6 Gran Coupe shares the same top-of-the-tree blown S63 TwinPower V8 as the other M6 variants and M5 sedan, producing 412kW of power and 680Nm of torque.

BMW’s seven-speed dual-clutch automatic transmission is also standard fare on the new arrival, driving the rear wheels.

If customers ask for the electronically controlled 250km/h speed limiter to be switched off, the M6 Gran Coupe is said to be capable of 305km/h.

The front styling of the M6 Gran Coupe is almost identical to that of the other M6 models, with the enlarged air scoops and LED headlamps all replicating the existing cars.

However, images released by BMW seem to show chrome-finished vertical slats in the kidney grille in place of the gloss black items on the coupe and convertible.

At the rear, the boot-mounted high-level stop light of the two-door cars has been repositioned into the rear window for a cleaner finish. The quad exhaust pipe outlets have been retained.

The M-enhanced Gran Coupe weighs in at a hefty 1950kg – 5kg heavier than the M5.

However, like the M6 Coupe, the four-door M6 benefits from light-weight construction, including a carbon fibre-reinforced plastic roof with a distinctive dip down the middle. In the coupe, that roof is said to save 20kg over a steel equivalent.

Along with innovations such as idle-stop, the light-weighting helps to trim fuel economy to 9.9 litres per 100km/h – the same as the M6 Coupe and M5 and 0.4L/100km/h more efficient than the heavier M6 Convertible. Carbon dioxide emissions are 232 grams per kilometre.

To accommodate the rear doors and extra rear-seat legroom, the wheelbase is 113mm longer than that of the two-door models, sitting on the same 2964mm platform as the M5.

The M6 Gran Coupe is considered a four-seater, with BMW saying the two rear-seat passengers enjoy “generous levels of on-board comfort”.

The Munich company says a fifth person can be carried in the middle of the back seat for short distances, presumably because the hump in the middle of the bench is uncomfortably pronounced.

Driving aids include BMW’s Active M Differential with multi-clutch limited-slip torque distribution to the rear wheels and with M-tuned active dampers.

The M6 Gran Coupe retains tried-and-true hydraulic rack-and-pinion power steering, going against the trend to electric-assisted power steering.

The four-door M6 gets 20-inch alloy wheels – as do the two-door variants – along with leather trim, alarm and premium audio system.

The BMW ConnectedDrive package adds head-up display, rear-view camera with surround view, lane-departure warning, night-vision system with pedestrian warning and other goodies.