Crossing the Blues

Wednesday, January 16, 2008

OFFICIAL: BMW M3 Convertible Revealed


Page 1: Summary
Page 2: In Detail: Part 1
Page 3: In Detail: Part 2
Page 4: In Detail: Part 3
Page 5: Specifications


Six-speed manual gearbox perfectly matched to the V8 power unit.

The new BMW M3 Convertible comes as standard with a manual six-speed gearbox featuring gear ratios perfectly tailored to the high-speed concept of the eight-cylinder engine. With short gear lever travel like in motorsport and crisp, precise movement of the shift lever, the driver is able at all times to transmit the superior power and thrust of the V8 to the rear wheels with the ideal gear ratio.

Integrated, temperature-controlled oil cooling keeps the temperature of the transmission fluid within the right range even under extreme conditions – for example on the race track. The two-plate clutch optimised for mass inertia, in turn, is carefully matched to the superior power and muscular torque of the eight-cylinder. And the six-speed manual gearbox with all the features so typical of BMW M is likewise able at all times to optimise the superior potential of the new BMW M3 Convertible when accelerating and going for superior performance.

Special chassis and suspension for the dynamic performance typical of a BMW M3.

Like the BMW M3 Coupé and the BMW M3 Saloon, the new BMW M3 Convertible also features rear-wheel drive. This principle of splitting up steering and drive forces on the front and rear axle ensures ideal conditions for dynamic driving qualities, very good directional stability, and safe handling. From the start, therefore, the new BMW M3 Convertible offers the ideal configuration for a particularly agile high-performance sports car.

The new BMW M3 Convertible boasts a chassis and suspension tailor-made for the particular requirements and features of an open car. The “foundation”, of course, is provided by the chassis and suspension carried over from the BMW M3 Coupé appropriately modified for the specific weight distribution and the different roof on the Convertible. Like on convertibles in general, additional features have been integrated in the new BMW M3 Convertible to optimise its torsional stiffness. Compared with former generations of the BMW M3 Convertible, torsional stiffness particularly important to safety and driving dynamics has been significantly increased to an even higher standard, also taking the increase in engine output into account.

Benefitting from the demanding chassis and suspension, as well as the overall construction of the car, the new BMW M3 Convertible offers dynamic driving qualities quite comparable to the excellent driving features already ensured by the BMW M3 Coupé and Saloon.

Rear axle with reinforced suspension and modified air flow.

On the rear axle the V-bars already featured on the Coupé and Saloon to provide the necessary reinforcement have been extended all the way to the side-sills. This configuration enhances chassis stiffness around the rear axle and provides appropriate axle kinematics for a car with supreme engine power and sporting performance all round. In addition, the engineers at BMW M GmbH have modified the flow of air beneath the car at the rear to the change in design and construction, thus ensuring optimum cooling on the final drive.

In its overall construction, the five-arm rear axle is designed consistently for minimum weight. The anti-roll bar, for example, is a hollow tube in the interest of significant weight reduction. So despite the slightly larger diameter of the tube than on the Coupé, the anti-roll bar on the BMW M3 Convertible offers an ideal combination of superior efficiency and low weight. Together with the axle arms made of forged aluminium and the aluminium dampers, the reduction in weight ensured in this way adds up to approximately 2.5 kg.

The front axle assembly is the same as on the Coupé and Saloon, with nearly all components on the double-arm front axle made of aluminium. A high standard of lateral stiffness at the front reflecting the superior power of the engine is ensured among other things by extra-stiff spring struts, swivel mounts and axle supports specific to BMW M, and an additional light-alloy reinforcement panel beneath the engine. And like the anti-roll bar at the rear, the anti-roll bar on the front axle is also a tubular structure serving to optimise its functions and minimise its weight.

Compound brake system and forged light-alloy wheels.

The new BMW M3 Convertible comes with the same extra-large compound brakes as on the Coupé and Saloon. The inner-vented, cross-drilled grey-cast iron brake discs measuring 360 millimetres/14.2´´ in diameter at the front and 350 millimetres/13.8´´ at the rear are connected to the aluminium disc support by stainless-steel pins cast into position.

With this configuration significantly reducing the thermal loads acting on the brake discs, brake performance and service life are enhanced accordingly. A further advantage of this high-performance brake system is the additional reduction of weight where it really counts, that is on the car’s unsprung masses.

An ongoing, continuous wear indicator permanently monitors the condition of the brake pads, a display in the cockpit informing the driver of their remaining service life. This not only enhances safety on the road, but also avoids unnecessary service and maintenance.

The underpressure required for the brake servo is generated by an electrical pump independently of engine speed.

The new BMW M3 Convertible comes as standard on forged light-alloy wheels in BMW M design. Rim dimensions are 8.5 x 18 inches at the front on 245/40 low- profile tyres and 9.5 x 18 inches at the rear on 265/40 tyres.

Servotronic with two control maps for optimum steering power assistance.

The new BMW M3 Convertible comes with rack-and-pinion steering featuring hydraulic Servotronic support. Servotronic reduces the steering forces required, with the degree of power assistance related to the speed of the car on the road.
At low speeds, therefore, Servotronic provides a lot more steering support to reduce the steering effort, for example when parking. At high speeds, on the other hand, power assistance is reduced accordingly in the interest of enhanced directional stability.

Using the optional MDrive configuration system, the driver is able to pre-select the actual effect and assistance factor provided by Servotronic following either the Normal or the Sports control maps.

In the Sports setting, Servotronic gives the driver a particularly direct feeling for optimum feedback on road conditions. On winding country roads and at high speeds this enables the driver to steer the car with unparalleled precision. In the Normal mode, by contrast, power assistance is increased consistently throughout the entire speed range.

Variable M Differential Lock for perfect traction on the rear axle.

The new final drive features BMW’s variable M Differential Lock also on the BMW M3 Convertible. Generating up to 100 per cent locking action when required in a fully variable process, this special differential lock ensures optimum traction on all surfaces and in fast, dynamic bends.

The variable M Differential Lock responds to differences in speed between the left and right rear wheel and offers ideal support enhancing the positive qualities of rear-wheel drive to an even higher standard.

Dynamic driving programs in M-specific configuration.

Electronic dynamic driving programs support the driver in dynamic situations approaching the limits to driving physics. DSC Dynamic Stability Control, for example, offers an even wider range of functions on the new BMW M3 Convertible in the interest of enhanced driving safety. When necessary DSC will intervene specifically in the brakes on individual wheels and reduce engine power in order to maintain driving stability. Pre-loading of the brake pads serves, as another example, to give the driver valuable time when applying the brakes in an emergency and significantly shorten his stopping distances. Yet a further feature offered by DSC is regular Dry Braking not even noticeable to the driver, keeping the brake discs free of the usual water film on the surface when applying the brakes in the wet and thus avoiding any loss of brake power.

Dynamic Stability Control includes ABS anti-lock brakes, ASC Automatic Stability Control preventing the wheels from spinning on surfaces with reduced grip, a Start-Off Assistant preventing the car from rolling back when setting off on an uphill gradient, and CBC Cornering Brake Control reducing the risk of the car spinning or swerving out of control in a bend. A further feature of DSC is its ability to increase brake pressure whenever the brake system becomes extremely hot, thus maintaining a consistent level of brake power (Fading Compensation).

The behaviour and response of these dynamic driving programs is naturally tailored to the superior performance of the BMW M3 Convertible. The system thus intervenes with electronic precision in an appropriate style matched to the excellent dynamic qualities and supreme power of the car. A further point is the driver’s option to configure certain parameters individually, thus adjusting the response of the car to his personal preferences.

Pressing a button in the centre console, the driver is able to completely deactivate DSC Dynamic Stability Control, the particularly ambitious driver therefore being able in such a case to push the dynamic potential of his car to the utmost. So when driving this sports car on a race track, the experienced and ambitious specialist is able to reach the utmost limits to driving physics and enjoy all of the car’s dynamic power in bends.

Electronic Damper Control responding spontaneously to every change in driving conditions.

As an option the new BMW M3 Convertible may be equipped with EDC Electronic Damper Control. Adjusting damper forces electrohydraulically, EDC optimises both the car’s vertical vibration behaviour as well as its yaw and roll motion in bends and its dynamic axle load distribution when applying the brakes and when accelerating.

Like the engine control map, operation and implementation of Electronic Damper Control may be varied at the simple touch of a button on the centre console to the driver’s individual preferences, offering the driver the choice of three settings Normal, Comfort, and Sports. The range of damper adjustment covered in this way is far greater than with conventional systems of this kind.

Quite generally, the new BMW M3 Convertible offers a wide range of driving qualities and characteristics all the way from very dynamic to more comfortable. In the Sports mode, EDC keeps the body of the car and all movements particularly firm and almost rigid. Wherever the driver does not seek such a particularly sporting set-up, he can opt either for the Normal or for the Comfort mode. In such cases, depending on the set-up chosen, the system responds also to smaller bumps in the road by more sensitive behaviour and with longer damper travel.

A further point is that EDC follows an adaptive pattern in all operating modes, adjusting damper forces quickly and sensitively to any change in driving conditions. As soon as faster movement of the steering wheel and higher steering angle speeds indicate that the driver is opting for a more dynamic style of motoring on winding roads, damper forces are increased automatically, EDC possibly even reaching the maximum limit of damper force for a short spell under such conditions, regardless of the set-up currently chosen. This perfectly supports any spontaneous changeover from comfortable cruising to a more sporting and active style of motoring.

Offering qualities of this kind, EDC ensures that the chassis and suspension are able to perfectly handle the very different driving conditions and demands faced in such a high-performance convertible. Featured in the new BMW M3 Convertible, EDC thus offers the entire range of motoring qualities from smooth gliding at low speeds all the way to dynamic motoring in a most sporting style. And with optional MDrive, the driver is even able to save his preferred EDC set-up as part of the car’s individual configuration.

MDrive button on the steering wheel: enjoying the perfect set-up at all times.

On the new BMW M3 Convertible the iDrive control system may be enhanced as an option by an additional MDrive function. Using MDrive, the driver is able to access the engine and Servotronic control maps, the various modes of DSC, and, as a further option, the various EDC set-ups available. This gives the driver the possibility to pre-select his personal set-up for all dynamic driving systems open to configuration, thus enjoying “his” perfect set-up in accordance with his personal preferences.

The car configuration defined individually in this way is then saved and may be retrieved immediately simply by pressing the MDrive button on the multifunction steering wheel, regardless of the system setting previously chosen by way of the function buttons. This enables the driver to enjoy the versatile character of his car in every respect and with all its facets, changing to his personal set-up at the simple touch of a button.

MDrive also serves as an exclusive feature to activate the Sports Plus engine control map, the M Dynamic Mode within the DSC range, and the Sports Servotronic control map.

Torsionally stiff body as the foundation for superior occupant safety.

The extra-strong structure of the body with optimised torsional stiffness and restraint systems tailored to a convertible provides the foundation from the start for a high standard of passive safety and all-round occupant protection in the new BMW M3 Convertible. Especially the restraint systems are particularly flexible, being activated electronically according to current requirements and driving conditions.

The use of high-strength steel for the extra-large load-bearing structures, together with the exactly defined arrangement of deformation zones in the event of a collision, guarantees appropriate diversion and, respectively, absorption of the forces acting on the car. The space available for deformation is used in full in order to avoid damage to the passenger cell or keep any such deformation in the passenger area as small as possible even in a severe collision.

The airbags, belt latch tensioners and belt force limiters are activated by the central safety electronics as a function of the type and severity of a collision. Using sensors in the middle of the car, in the B-pillars and in the doors, the electronic safety “brain” determines which safety components will offer the occupants maximum protection, activating only those restraint systems actually required.

The driver and front passenger are protected by frontal and side airbags activated in two stages in accordance with the severity of a collision.
The head/thorax airbags at the side are integrated in the seat backrests and inflate in a side-on collision over a large area extending from the bottom of the backrest all the way to the top edge of the headrest. This gives the occupants optimum protection on their upper body and head, regardless of their personal seating position.

The side airbags protect both the body and the head of the occupant in the event of a collision from the side, while the risk of leg injury in a head-on collision is reduced on the driver’s side by predetermined deformation of the footrest.

The BMW M3 Convertible also comes with a rollover sensor system permanently monitoring vertical and horizontal movement of the car. At the same time a central computer evaluates data on current driving conditions, so that when the roof is open rollbars positioned behind the headrests are activated and move up immediately whenever the system registers the risk of a rollover. The belt latch tensioners for the front seats and the head/thorax airbags are activated at the same time, and as a further precaution for the event of a rollover the A-pillars and the windscreen frame are even stronger and more stable than usual.

The interior: enjoying freedom and dynamism for four.

The freedom of driving in the open air and the dynamic performance of a BMW M3 – in the new BMW M3 Convertible this is a outstanding experience for up to four occupants. The front seats feature integrated belt systems, while the centre console extending all the way to the back splits the rear seat bench into two separate seats with generous headroom. In comparison with the former model, shoulder room at the rear is up 9 centimetres or 3.5´´, elbow room has been increased by an even more significant 11 centimetres or 4.3´´.

Access to the rear seats is facilitated by the Easy Access function on the front seats, and the seat release lever is arranged in its ideal ergonomic position at the top on the outside of the backrest.

The new BMW M3 Convertible proves its superior touring qualities also through unusually variable storage capacities and options. Even with the roof open, the luggage compartment still offers capacity of 210 litres or 7.35 cubic feet, enough for a large hard-shell suitcase or up to two golf bags.

The rear compartment in the Convertible may also be used as additional storage space. In this case, after folding down the single-piece rear seat backrest, the driver and front passenger are able to load even bulky objects on the flat surface without the risk of soiling, let alone damaging, the seat upholstery.

A feature quite unique in a convertible of this calibre is the optional opening between the luggage compartment and the passenger area measuring about 40 centimetres or almost 16´´ in width. Clearly, this is ideal for through-loading long objects such as skis, snowboards or golf bags from the luggage compartment into the rear passenger area.

Qualities of this kind make the new BMW M3 Convertible the ideal car for the driver and passenger travelling alone and enjoying superior versatility in every respect. But even when all four seats are occupied, this through-loading facility connecting the luggage and the passenger compartments may be used conveniently thanks to the large opening between the rear seats.

The opening and closing mechanism for the retractable hardtop is activated by a switch in the centre console. A further possibility is to open the hardtop by remote control from the central locking.

Enhanced remote control with comfort access is available as an option, enabling the driver to start the car without even using a key and offering the possibility to close the hardtop from a distance.

To avoid any inadvertent activation of the hardtop, this signal to close the roof is transmitted to the car only up to a distance of four metres or just over13 feet at the very most.

Comfort access also allows particularly convenient loading and unloading of´the luggage compartment with the roof open. In order to improve access to the luggage compartment in such a case, the hardtop, when open, is moved by remote control to an interim position enabling the driver to conveniently take out large objects such as golf bags.

The process of loading the car is also facilitated by the variable panel separating the roof from the luggage compartment. With the hardtop closed, this cover may be swivelled up electrically, enlarging luggage space to a volume of up to 350 litres or 12.25 cubic feet.

The cover panel is activated by a switch in the centre console of the car. Once it has been lowered, the new BMW M3 Convertible can start to convert into an open-air model. The luggage compartment lid, in turn, comes with a Soft-Close function smoothly and gently pulling the lid into position in an automatic process after loading and unloading.


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