The iconic BMW M5 Sedan and M6 Coupe went on sale in the US in August 2012 after a two year hiatus. They are more powerful, more athletic, more luxurious and more efficient than ever before. They join the all-new BMW M6 Convertible which first arrived in US BMW Center showrooms in July 2012. For more than a quarter century, the BMW M5 and M6 have exemplified the luxury and daily versatility of a true BMW combined with all-out supercar performance.
The BMW M5 and M6 are ultra-high-performance sports cars with exceptional dynamic abilities which have been carefully tuned by M engineers on racetracks around the world under all conditions. Simultaneously, the BMW M5 and M6 bring new standards for daily driving comfort and features. To achieve these lofty goals, the new BMW M5 Sedan, M6 Coupe, and M6 Convertible share the most powerful engine ever fitted in a series-produced model from BMW M GmbH mated to a high-torque 7-speed M-Double Clutch Transmission (M-DCT). An innovative Active M Differential further splits power transfer between the rear wheels. This drivetrain, combined with extensive chassis and suspension upgrades ensure that the engine's performance can be transferred to the ground.
The engine: High-Revving V8 Engine with M TwinPower Turbo Technology
The new engine shared by the BMW M5 and M6 has the highest output ever generated by a BMW M car, and at the same time provides the most efficient balance between performance and fuel consumption. It is characterized by immediate throttle response, a linear power band and an unusually high and flat torque curve. The new engine produces around 10% higher output than the V10 engine of its predecessors and torque is up by over 30%. At the same time, fuel efficiency has improved by nearly 25 percent.
To achieve the performance levels demanded by the BMW M5 and M6, the engineers at BMW M started with the proven BMW M developed V8 engine from the BMW X5 M / X6 M (internally known as the S63) and further developed it for its duty in the latest M5 and M6 models. Internally designated as the S63Tü this new engine uses similar M Twin Power technology combined with the reverse flow V8 layout. The result is that the high-revving V8 engine with M TwinPower Turbo Technology lends a whole new intensity to the powerful thrust at higher rev ranges for which M cars are known. The 4.4-liter engine develops a peak output of 560 hp (412 kW) at 5,750 - 7,000 rpm (versus 555 hp at 6,000 rpm for the S63), while its maximum torque of 500 lb-ft (680 Nm) is on tap between 1,500 and 5,750 rpm (versus 500 lb-ft from 1,500 to 5650 rpm for the S63). The rev limiter intervenes at 7,200 rpm (up 200 rpm from the S63 engine). The rev band, which offers extremely dynamic acceleration between peak torque and the availability of maximum output, is therefore almost three times as wide as that of the V10 engine in the previous generation M5/M6.
As in the V-8 engine of the X5 M, the two twin-scroll turbochargers, along with the catalytic converters, are placed in the V-space between the two cylinder banks in a reverse flow layout. This layout results in an unusually compact engine where the intake is moved outboard and the exhaust inboard - the opposite of conventional V-engines. The lengths of intake and exhaust tracts are thereby reduced and their diameters increased, reducing pressure losses - especially on the exhaust side. A further advantage of the layout is the short distance between the cylinders' combustion chambers and the primary catalytic converters; this leads to quicker warm-up of the catalysts after the engine is started and therefore lower start-up emissions.
The patented cross-bank exhaust manifold, first introduced in the S63 engine of the X5 M / X6 M is also employed in the S63Tü. This exhaust manifold is a special 8-into-4 setup that combines the exhaust from two cylinders (on opposite banks) that are 360 degrees of crankshaft rotation apart from each other. Each of the eight runners is of identical length to ensure perfectly regular timing of exhaust gas pulses.
Each of the four manifold outlets is fed into each of the four available scrolls of the two twin-scroll turbochargers. The two scrolls of a twin-scroll turbo lead each exhaust pulse directly to the turbine without feedback or interference from the other scroll (that are fed by cylinders at other points in the combustion process). Additionally, dividing the gases into two smaller paths (scrolls) results in higher gas velocity than a single larger path. This enhances the turbocharger's response thereby reducing lag. The crossover manifold is configured so that the second scroll of the turbo is fed by two cylinders that are 180 degrees out of phase with the first scroll. In this way each turbocharger receives distinct exhaust pulses every 180 degrees of crankshaft rotation (from one of four cylinders). Furthermore, the two turbos receive exhaust pulses that are 90 degrees offset from each other. The result is that throttle response is sharpened and turbo lag is reduced to a minimum. The new engine also sports larger intake runners, larger air to liquid intercoolers and a tuned exhaust which results in the engine making power more quickly than previously possible. Finally, the S63Tü uses a maximum boost pressure of 1.5 bar (21.7 psi) versus 1.2 bar (17.4 psi) for the S63 engine.
BMW's efficient High Precision direct fuel injection also plays a major role in this engine's combination of high performance and fuel efficiency. High Precision direct fuel injection ensures an extremely precise supply of fuel to the combustion chambers. Injectors positioned centrally between the valves within immediate range of the spark plugs spray the fuel into the combustion chambers with maximum pressure of 200 bar (nearly 3000 psi), providing smooth and clean combustion. Innovative solenoid valve injectors in the new BMW M5/M6 engine use multiple injections per combustion cycle to achieve an extremely precise mixture preparation. The fuel also has a cooling effect on the combustion that allowed the M engineers to endow the engine with a high compression ratio of 10:1. This high compression ratio contributes to both performance and efficiency, while reducing exhaust emissions - and even has a positive effect on engine sound.
Throughout its history, the heart of the BMW M5 and M6 has been its high-revving, high output-per-liter engine fed by individual throttle plates. The new engine introduces VALVETRONIC variable valve control system to a BMW M engine - effectively providing 16 individual throttles.
VALVETRONIC is BMW's patented fully variable valve control system that eliminates the need for conventional throttles. Engine power is instead controlled directly by varying the amount of lift of the intake valves. Pumping losses are minimized with this system and resulting in efficiency and torque improvements. VALVETRONIC has also sharpened the responsiveness of this engine compared to the V10 engine it replaces.
The M TwinPower Technology of the new V8 engine also includes BMW's Double VANOS infinitely-variable valve timing system which optimizes the engine's efficiency and generates high torque at low engine revs. In addition, a volume-controlled oil pump and a range of other EfficientDynamics measures deliver an extra boost to efficiency. The new BMW M5 and M6 feature both Brake Energy Regeneration and the Auto Start-Stop function, which automatically switches off the engine when the car comes to a stop.
The engine's exhilarating thrust gives both models impressive acceleration. The instant power delivery and sustained thrust of the engine results in acceleration of 0 - 60 mph in 4.1 seconds for the Coupe and 4.2 seconds for the Convertible. The top speed of both models is electronically limited to 155 mph (250 km/h). The sprint for the BMW M5 from rest to the 60 mph (0-100 km/h) mark is all over in 4.2 seconds (4.3 for the 6-speed manual) and from that point progress continues with barely any let-up. Maximum speed is electronically restricted to 155 mph (250 km/h). While the engine's output has increased by around 10% and maximum torque is up by more than 30%, the new BMW M5 and M6 models consume roughly 25% less fuel and have a highway range about 34% higher than their predecessors.
M TwinPower Turbo Technology also shapes the development of the V8 engine's soundtrack. The concept of crossover exhaust manifolds plays a key role in delivering a multi-layered collage of sound. The twin-tailpipe exhaust system of the new BMW M5 and M6 runs largely in a straight line and has a large cross section. The two exhaust pipes feed into a single muffler from which the customary M quad tailpipes extend out through the far left and right-hand sides of the rear diffuser.
7-speed M Double Clutch Transmission with Drivelogic
The new V8 engine M TwinPower Turbo engine is mated to a newly developed 7-speed double-clutch transmission designed to handle the high torque and high revving nature of the engine. The M DCT with Drivelogic System developed especially for the new M5 and M6 has been tuned to the performance characteristics of the engine. It delivers exceptionally fast and clean gear changes in both automatic mode (D) and manual mode (S). No clutch pedal is required for manual gearshifts and the driver can keep their foot on the accelerator during gear changes. The driver uses the model-specific M gear selector to choose between D and S mode and to engage reverse. 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.
The transmission offers a sequential shift pattern for the manual gearshift mode. Alternatively, the driver can also change gears manually using the shift paddles on the newly developed M leather steering wheel, complete with multifunction buttons. In typical M configuration, the driver pulls the right-hand paddle to shift up and the left-hand paddle to shift down. The new M steering wheel stands out with its smaller rim diameter and a design that borrows from the double-spoke design of the M light-alloy wheels.
M DCT with Drivelogic offers three shift programs in both automatic and manual modes. The driver selects his/her desired mode using the rocker switch positioned immediately below the shift lever on the center console. The D1 program is selected automatically when the engine is started, tailoring gear selection to deliver the most efficient possible driving style. D2 mode supports laid-back cruising with gear changes carried out according to engine revs and load. And, to promote a sporty driving style laced with dynamic acceleration, shift times in D3 mode are set up to delay gear changes until the engine has climbed 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. In S2, the gear changes are completed noticeably faster and accompanied by significant shift kick at higher revs. S3 is the one to choose for maximum driving dynamics; it enables even 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 gear shift takes place automatically and at the optimum engine speed.
Active M Differential
The Active M Differential in the new BMW M5 and M6 is an electronically controlled multi-plate limited-slip differential programmed to optimize traction, stability and sporting character.
The rear axle's multi-plate limited-slip differential works with high precision and speed. Its control unit is connected with the Dynamic Stability Control (DSC) system via FlexRay high-speed data transfer technology and constantly cross-checks the data collected by its sensors with the feedback from DSC. It then uses this information to calculate the locking force required to deliver optimum traction and stability. The data recorded by DSC sensors is also passed on if the stability control system is switched off. The locking force within the differential can be varied continuously between 0 and 100%. The ABS system retains full functionality in all situations.
In addition to its own data and that provided by DSC, the Active M Differential's control unit also takes into account the position of the accelerator pedal, the rotational speed of the wheels and the car's yaw rate. Every driving situation is therefore analyzed so that any loss of traction on one side of the car is identified at an early stage. The degree of lock is adjusted as required within a fraction of a second, enabling wheel spin to be prevented on slippery surfaces, when the right and left rear wheel have widely differing friction coefficients and in tight corners. Optimizing traction in this way also provides unbeatable driving stability in challenging conditions and allows impressive dynamic acceleration out of corners.
M-Specific Chassis
Each component in the suspension and chassis of the new BMW M5 and M6 has been developed based on the extensive race expertise of BMW M engineers. In both models, the integral rear axle subframe is directly bolted to the body to maximize body rigidity and handling precision. Reinforced chassis mountings for the front and rear suspension ensure that dynamic forces are passed through to the body structure. Specially tuned axle kinematics and newly developed forged aluminum suspension components boasting impressive strength and minimized weight meet both the requirements of everyday road driving and the specialized demands of track use. The result is that the BMW M5 and BMW M6 continue the BMW M tradition of engineering a chassis that is "faster than the engine". As with every BMW M car, the engineers carried out the fine-tuning during extensive testing on the Nürburgring Nordschleife circuit.
Dynamic Damper Control (DDC) electronically controlled shock absorbers are standard on the new BMW M5/M6. DDC uses electro-hydraulic damping force adjustment to provide a set-up suited to the driving situation and the wishes of the driver. The shock settings can be adjusted at the touch of a button. In "Comfort" mode, they respond adaptively to the condition of the road surface and the driver's style. "Sport" mode activates a noticeably stiffer damper set-up, while "Sport +" allows further stiffening of the suspension to achieve maximum longitudinal and lateral acceleration in ultra-dynamic driving situations.
At the touch of a button, the driver can also select from three settings for the M-specific Servotronic speed-sensitive power steering. "Comfort" mode requires only a small amount of steering force when parking or maneuvering, but still provides the M brand's hallmark direction-changing precision at higher speeds. "Sport" ensures the driver enjoys more intensive feedback across all speed ranges. "Sports Plus" is the highest level of steering dynamics that can be selected where the driver is called on to use even greater force with the steering wheel.
The new BMW M5 and BMW M6 also use BMW's most advanced Dynamic Stability Control (DSC) and Anti-lock Braking System (ABS) that include Cornering Brake Control (CBC), Dynamic Brake Control (DBC), Brake Assistant, brake fade compensation, a Brake Drying function and Start-off Assistant. The DSC system has three levels of operation. The default is "DSC On" which provides the greatest level of stability and traction control. M Dynamic Mode (MDM) can be activated to override the basic setting by pressing the DSC button on the center console. This mode allows for very spirited driving - as on a race track - while still providing a safety net, by raising the intervention thresholds of DSC. "DSC Off" mode can also be activated at the touch of a button for complete deactivation of the system.
High-Performance Brake System
The high-performance braking system of the new BMW M5 and BMW M6 guarantees outstanding stopping power matching the overall performance of the car. The typical BMW M compound rotors have been further improved for the new M5 and M6. These rotors thermally separate the central hub, which is constructed of aluminum for reduced unsprung weight, and the vented/cross drilled cast iron rotors. As a result, the rotors are free to expand and contract without warping. The six-piston fixed calipers are radially bolted to the pivot bearing and are painted dark blue metallic complete with the M logo. Together, the brake system has been tested to provide exceptional performance, fade resistance and pedal feel.
The standard BMW M5 wheel and tire combination is a19 in. M specific light alloy wheels fitted with 265/40 R19 tires in the front and 295/40 R 19 tires at the rear. 20-in. forged M light-alloy wheels can be ordered as an option. The standard M6 wheel and tire combination is a 19 inch M specific light alloy wheels fitted with 265/40 R19 ultra-high performance summer tires in the front and 295/35 R 19 tires at the rear. 20-inch forged M light-alloy wheels can again be ordered as an option.
The new BMW M6 Coupe and Convertible will be the first cars in the history of BMW M to be offered with optional M Carbon-Ceramic brakes (available in 2013). These new brakes are without parallel and take the cars stopping power to another new level - especially at the race track. The brake rotors measure 16.1 inches (410 mm) in diameter at the front and 15.6 inches (396 mm) at the rear. Made from a carbon-fiber ceramic compound, the rotors boast even greater resistance to heat combined with significantly reduced rotating masses. The M Carbon-Ceramic brakes are 42.8 lb (19.4 kg) lighter than the standard brakes, yet the innovative material also displays exceptional resistance to wear, and the operating life of the rotors is many times that of conventional equivalents. The optional M Carbon-Ceramic system also sees six-piston fixed radial calipers at the front teamed with single-piston floating calipers at the rear. The M Carbon-Ceramic system can be easily identified through the wheels by the special gold-colored calipers.
