BMW is claiming this to be the third generation of M6 vehicles, tracing its origins back to the original 1987 E24 model, even though it only bore the M635csi designation in Europe.
Pedantics aside, owners of the previous V10 model should appreciate 10% more power with 30% more torque, yet fuel consumption and emissions are reduced by 30%.
As we said, it does this with the M5’s V8, which in turn is based on the S63 motor found in the X5 M and X6 M SUV models. A higher rev limit (200rpm more at 7200rpm), software, exhaust and intercooler changes allow the revised engine (known as S63Tü). It also develops slightly more boost –21.7psi against 17.4psi for the S63. This allows it to produce 560hp at 5750rpm (versus 555hp at 6000rpm for the S63). Maximum torque is the same at 500 lb-ft but it runs to 5750rpm versus 5650rpm in the SUVs.
The instant power delivery results in acceleration figures of 0-62mph in 4.2sec for the Coupe and 4.3sec for the Convertible. The sprint from 0–124mph (0-200km/h) takes only 12.6sec for the Coupe, 13.1 for the Convertible. The top speed of both models is electronically limited to 155mph.
Both 4.4-liter engines use a similar reverse-flow V8 layout where the two twin-scroll turbos are placed in the vee between the cylinder heads (along with the cats). This results in an unusual engine where the intake is moved outboard and the exhaust inboard. The lengths of intake and exhaust tracts are therefore reduced and their diameters increased, reducing pressure losses on the exhaust side. A further advantage is a quicker warm-up of the cats to reduce cold-start emissions.
The direct fuel injection also plays a role in the combination of high performance and fuel efficiency. The injectors spray fuel at a maximum pressure of nearly 3000psi, with new solenoid valve injectors allowing multiple injections per combustion cycle to achieve a precise mixture. The fuel also has a cooling effect on the combustion process, making a 10:1 compression ratio possible.
Other engine technologies include individual throttle plates and BMW’s Valvetronic variable valve control system as well as the Double Vanos variable valve timing system. In addition, a volume-controlled oil pump and a range of other EfficientDynamics measures deliver efficiency, such as Brake Energy Regeneration and Auto Start-Stop.
The new V8 is mated to a newly developed seven-speed double-clutch transmission designed to handle the high torque of the engine. The M DCT with Drivelogic System has been tuned to the performance characteristics of the engine. It delivers fast changes in both automatic mode (D) and manual mode (S) using the shift lever of paddles. No clutch pedal is required for manual gearshifts and the driver can keep their foot on the accelerator during gear changes. Comfort is further enhanced by the new Low Speed Assistance function, which smoothes power delivery in stop-and-go traffic with a light touch of the accelerator pedal.
M DCT with Drivelogic offers three shift programs in both automatic and manual mode. The driver selects the desired mode using the rocker switch below the shift lever. The D1 program is selected automatically, tailoring gear selection to deliver the most efficient possible driving style. D2 supports laid-back cruising with gear changes carried out according to engine revs and load. And, to promote a sporty driving style, shifting in D3 mode allows the engine to climb higher up the rev range.
Drivers can also adapt the shift characteristics to their requirements in Manual mode. S1 mode generates comfortable and smooth gear changes. S2 is noticeably faster and accompanied by significant shift kick at higher revs. S3 enables sportier gear changes and is required to initiate the Launch Control function.
When the stability control system is switched off, Launch Control allows the driver to achieve maximum acceleration from a standstill as permitted by conditions. During Launch Control acceleration, each gearshift takes place automatically and at the optimum engine speed.
The Active M Differential in the new M6 is an electronically controlled multi-plate limited-slip diff programmed to optimize traction, stability and sporting character.
The LSD control unit is connected to the Dynamic Stability Control (DSC) system via FlexRay high-speed data transfer technology and cross-checks data collected by its sensors with feedback from DSC. It then uses this information to calculate the locking force required to deliver optimum traction and stability. The locking force of the differential is varied continuously between 0-100%.
The data provided by DSC to the Active M Diff also accounts for throttle position, wheel speed and the car’s yaw rate. Every driving situation is analyzed so any loss of traction is identified at an early stage. The degree of diff lock is adjusted as required within a fraction of a second, enabling wheelspin to be prevented on slippery surfaces and in tight corners.
The integral rear axle subframe of the M6 is rigidly bolted to the body to maximize rigidity and handling precision. Reinforced chassis mountings at the front and rear axles ensure dynamic forces are passed through to the body structure. New forged aluminum suspension components boast strength and less weight to meet the requirements of everyday driving and the demands of track use.
Dynamic Damper Control (DDC) is standard on the new BMW M6. It uses electro-hydraulic damping force adjustment to provide the best set-up for the driving situation. The shock settings can be adjusted to “Comfort” mode, where the dampers respond to the condition of the road and the driver’s style. “Sport” activates a stiffer set-up, while “Sport Plus” allows further stiffening achieve maximum acceleration.
At the touch of a button, the driver can also select three settings for the M-specific Servotronic speed-sensitive power steering. “Comfort” requires only a small amount of steering force when parking, but provides precision at higher speeds. “Sport” ensures the driver enjoys more feedback across all speed ranges. “Sports Plus” is the highest level of steering dynamics where the driver needs to use greater force on the wheel.
The brake rotors separate the central aluminum hub from the vented/cross-drilled rotors to avoid warping. They are 15.7” on the front and 15.6” rear, with six-piston calipers radially bolted to the pivot bearing and painted dark blue with the M logo.
The new BMW M6 will be the first BMW to offer the option of M Carbon-Ceramic brakes (in conjunction with 20-inch M wheels from July 2012 production). The rotors are 16.1” at the front and the whole system is 42.8 lb lighter than the standard brakes. The M Carbon-Ceramic system can be easily identified by the gold calipers.
The standard two-tone M6 wheel and tire combination is a 19” M wheel fitted with 265/40 R19 summer tires on the front and 295/35 R19 rears. 20” forged wheels can be ordered as an option.
M styling cues include new M kidney grilles, with an “M6” badge. The grille’s black, kidney grille slats are said to be fashioned after the wheels. While the 1.2” increase in track width is accommodated by flared front wheel arches.
The front fenders feature M gills with wide chrome frames and indicator bars with the M logo. The side skirts sweep upwards to the rear wheels.
At the rear, the familiar M quad exhaust tailpipes are positioned on either side of the diffuser .
Like its predecessor, the roof of the M6 Coupe is molded from carbon fiber composite. The lightweight material allows the center of gravity to be lowered, enhancing agility.
The weight is further minimized by the use of high-tensile and ultra-high tensile steel, as well as aluminum – The hood and doors, for example, are made of aluminum. While the front fenders are molded from thermoplastic. Furthermore, the trunk lids, and the Convertible’s roof compartment cover, are made from glass fiber composite material SMC (Sheet Molding Compound).
With a power-to-weight ratio of 7.3 lb/hp for the Coupe and 7.7 lb/hp for the Convertible, both models represent a substantial improvement over their predecessors.
The standard High-gloss Shadow Line trim surrounds the side windows as well as the M mirror caps.
Customers can chose from one non-metallic and eight metallic paint colors (including four exclusive M finishes). The soft-top on the Convertible is available in Black, Beige or optional Anthracite Silver effect.
The M-specific cockpit design includes newly developed M sports seats, Merino extended leather upholstery, door sills with “M6” lettering, an M driver’s footrest, exclusive carbon fiber interior trim and Anthracite headliner as standard equipment, as well as the iDrive control system with a 10.2” Control Display.
The new lightweight seats with integrated belt system have prominent cushion and backrest bolsters as well as integrated head restraints and eye-catching stitching plus an M logo embossed into the shoulder area.
The instrument cluster with black-panel-technology includes classic circular instruments with red needles and white illumination, plus the M logo on the rev counter.
On the left-hand steering wheel spoke, the driver has two M Drive buttons for a pre-configured setup. For example, the driver can save a sporty configuration on the “M1” button and a track focused setup with the driver aids off)on the “M2” button.
The M Drive system in the new M6 allows the driver to adjust no fewer than six parameters: the engine management, Servotronic steering, M DCT shift program, DSC mode, DDC responses and the Heads-Up Display. The desired settings are configured via the iDrive menu or by using the M Drive select buttons on the center console to set the configuration followed by pressing and holding one of the two M Drive buttons for a few seconds.
US Pricing, technical specification, EPA mileage ratings, standard and optional equipment will be announced closer to the on-sale date.