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M6 Cabrio - E64 (2006 - ...) - M Differential Lock

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M6 Cabrio - E64 (2006 - ...)
Muscular, sporting, elegant
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M Differential Lock
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M Differential Lock for extra safety and driving pleasure.
The final drive features BMW’s Variable M Differential Lock. Whenever required, this unique drive unit is able to generate up to 100 per cent locking action, optimising both driving stability and traction particularly when accelerating out of a bend, for example when one of the drive wheels is about to lock. Whenever the driver prefers a more sporting and dynamic style of motoring and on roads with a high frictional coefficient, the M Differential Lock also enhances the positive qualities of rear-wheel drive, thus offering extra safety and driving pleasure at all times. On a conventional, torque-sensing differential lock the overall drive force and engine power conveyed to the road depends on the traction maintained by the wheel with the lowest level of friction on the road surface, that is the wheel slipping most. Clearly, this often limits traction most significantly particularly on snow, gravel or ice. The engine speed-sensing Variable M Differential Lock, on the other hand, gives the car a decisive increase in traction even on road surfaces varying most significantly in their frictional coefficient – in extreme cases even conveying all the power and momentum of the engine via the wheel with the better frictional coefficient. Clearly, this gives the BMW M6 Convertible unusually good driving qualities in winter, the Variable M Differential Lock immediately building up increasing locking action between the drive wheels with an increasing difference in wheel rotation speed. This means that a wheel no longer conveying the full power of the engine – for example the inner wheel in fast bends – does not lead to a complete reduction of drive forces in an attempt to prevent the wheel from spinning. Instead, locking action is always controlled individually as required and drive power as well as traction are suitably maintained at all times.

DSC in M Configuration for enhanced safety.
The chassis and suspension of every BMW M model ensures superior dynamism and safety under all kinds of everyday driving conditions. Exceptional situations reaching the very limits of driving physics, in turn, are handled and optimised by BMW Dynamic Stability Control (DSC) permanently monitoring the car’s driving conditions and intervening whenever necessary in engine management in order to reduce drive forces or activate the brakes on a specific wheel. DSC thus enhances driving safety for example on a slippery road, in abrupt manoeuvres, or with the car threatening to lose stability in a bend. In the BMW M6 Convertible DSC Dynamic Stability Control is perfectly tailored to the car’s weight and centre of gravity. It also incorporates a specific M configuration enabling the driver to choose various dynamic driving programs by means of the special MDrive control unit. So while the first stage of DSC is fundamentally the same as on the BMW 650i Convertible, the M Dynamic Mode (MDM) caters for the sports-minded, truly ambitious driver. Indeed, this exclusive, supplementary function offers the sports motorist an entirely new dimension of driving dynamics, allowing him to enjoy the car’s maximum straight-ahead and lateral dynamics simply at the touch of a button on the MDrive control unit. Enjoying this exclusive option, the driver will really experience the utmost limits of driving physics, DSC not intervening until the car reaches the ultimate point on the road and thus allowing the driver to handle the greatest possible power slide by slight countersteering on the steering wheel. A warning signal in the instrument panel tells the driver that the M Dynamic function is active. And last but not least, the driver is able to completely deactivate DSC, as on all BMWs.


Power button for individual control of engine characteristics.
Last but certainly not least, the BMW M6 Convertible also reveals its supreme qualities in fast but relaxed motoring. In other words, the driver does not always require all the power of the V10 in order to enjoy exceptional driving pleasure under all conditions. Precisely this is why the extra-comfortable P400 performance program is automatically activated when starting the engine, offering initial engine power of 400 hp. Then all the driver has to do is press the MDrive button on the steering wheel or the Power button on the selector lever cover in order to enjoy the full 507 hp developed by the engine, with the gas pedal kinematics becoming even more responsive and spontaneous, ensuring extremely sporting and dynamic driving pleasure in the P500 program and, even more so, in the P500 sports program.

EDC Electronic Damper Control: from sporting and firm all the way to comfortable and smooth.
EDC Electronic Damper Control provides permanent, infinite electronic adjustment of the dampers. Simply pressing the MDrive button, the driver is able to choose the characteristics of the suspension in three steps from sporting and firm all the way to comfortable and smooth. Compared with the BMW M6 Coupé, damper adjustment is somewhat more oriented to motoring comfort, thus reflecting the character of the Convertible designed and conceived for supreme style and refinement on the road. In the sports program, on the other hand, the suspension set-up and characteristics are almost the same as on the Coupé. A further advantage of EDC is that the car’s vibration qualities and ride smoothness are maintained consistently at all times, regardless of current load conditions and throughout the entire lifecycle of the BMW 6 Series Convertible.

High-performance brakes like in motorsport.
Reflecting its supreme power and performance, the BMW M6 Convertible naturally boasts a high-performance brake system with weight-optimised compound brake discs measuring 374 x 36 millimetres (14.72 x 1.42´´) at the front and 370 x 24 millimetres (14.57 x 0.94´´) at the rear. Double-piston swing callipers made of aluminium optimise both weight and stiffness, reducing unsprung masses and thus enhancing both the car’s driving agility, motoring safety and driving comfort. The result of this technology is impressive stopping power and deceleration, the BMW M6 Convertible coming to a standstill from 100 km/h within 36 metres or 118 feet and just under 140 metres or 459 feet from a speed of 200 km/h. Continuous, ongoing control of brake pad wear ensures lasting efficiency and function of the brake system maintaining its full quality at all times and under all conditions. In this case a sensor in the brake pads determines current wear conditions and transfers the information received to the DSC control unit serving, in turn, to monitor the current condition of the brake pads and specify the remaining mileage until new pads are required as a function of the driver’s personal style of motoring. This information is used for BMW’s Condition-Based Service (CBS) in order to determine when service and maintenance is required.

The wheels: light and good-looking.
Due to its large brake discs alone, the BMW M6 Convertible comes on extra-large and muscular wheels. The standard configuration is exclusive 19-inch forged aluminium wheels featuring five contoured double spokes for particularly graceful and delicate looks – and indeed, each of these wheels is 1.8 kilos or almost 4.0 lb lighter than a conventional cast aluminium wheel. As an option, the Convertible is also available with aluminium wheels in radial-spoke styling already featured on the BMW M5. On dry and wet roads, tyres measuring 255/40 ZR 19 at the front and 285/35 ZR 19 at the rear transfer high lateral and longitudinal forces to the surface with optimum precision. Despite their high standard of roll comfort, these tyres provide optimum feedback to the driver, keeping the car perfectly on track all the way to the most extreme limit.


Tyre repair system taking the place of a spare wheel.
The tyre repair system consists of a Tyre Defect Indicator and the M Mobility System (MMS) warning the driver through both an optical and acoustic signal of any sudden or gradual loss of pressure in one of the tyres. The special hump geometry of the rims, in turn, keeps even a completely empty tyre on the wheel, enabling the driver to come to a standstill safely and securely even in such a situation. The M Mobility System is housed conveniently in a compact box in the luggage compartment of the BMW M6 Convertible and serves to seal holes in the tyre of up to 6 millimetres in size. In practice, this allows the driver to repair nearly all punctures without having to change the wheel. The decision thus taken to do without a spare or emergency wheel saves more than 20 kilos or 44 lb in weight now no longer required.

Last Updated on Monday, 12 April 2010 14:37  

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