Press Release Part 1: The ultimate in sports saloon motoring has got a name: M5

This finest 5 Series vehicle is the most powerful of all time: five litres of cubic capacity, ten cylinders, a maximum output of 507 bhp (373 kW), a peak torque of 520 Newton metres and engine speeds redlining at 8,000 rpm, these are figures that speak for themselves. In an unprecedented way, these figures blur the lines between a car for everyday use and a vehicle for ambitious motor sport racing.

A successful recipe for two decades: power without overstatement.

With its performance figures, the fourth-generation M5 once again sets the benchmark in the segment of powerful sports saloons, a niche which the first M5 carved for itself back in 1984. During the last 20 years, this first M5 and all its successors have made their mark, always setting the standard as a perfect symbiosis of a comfortable, elegant saloon for everyday use, abundant output delivered by a powerful engine and ultimate sportiness.

With sales figures exceeding 20,000, the M5 has proved to be an economically successful concept which combines prodigious performance with understatement, a basic feature of all M automobiles.

This principle reaches its culmination in the new M5: this “extreme athlete” with its subtle appearance and the seemingly endless power of its ten-cylinder high-revving engine, which interacts perfectly with the seven-speed SMG gearbox, introduces the driver to completely new dimensions of effortlessness. To put it in a nutshell: in its class, which it shares with top-class competitors, the M5 excels due to the most innovative drive concept, the best power-to-weight ratio, supreme handling and excellent everyday driving qualities. It is a fully roadworthy saloon with the heart of an athlete, a sports car which is perfectly suited for everyday motoring. The new M5 skilfully combines these two virtues.
First high-revving V10 engine to be featured in
a regular-production saloon.

The V10 is the only high-revving power unit to be featured in a series-production car. Featured in the most powerful production car within the BMW model family, this new engine once again sets the benchmark in its class.

There is, however, more to it than pure performance. What is important for M automobiles is acceleration and driving dynamics, the latter which is dependent on the actual forward thrust and the vehicle’s weight. The drive forces at the driven wheels are significantly influenced by the engine
torque and the total ratio. The high-revving concept caters for an optimum transmission and rear-axle ratio, thus guaranteeing an impressive forward thrust.

The perfect choice: high-revving concept.

For the BMW M engineers the compact, high-revving normally aspirated engine was the ideal choice. With a red line of 8,250 rpm, the ten-cylinder engine has ventured into terrain which has so far been reserved for red-blooded racing cars. Compared to the previous M5 eight-cylinder engine, performance has increased by more than 25 percent. The M5 has also surpassed the magical 100 bhp per litre limit, its specific output being on par with that of racing cars.

A masterpiece in engine construction.

The two five-cylinder banks of the V10 are arranged at an angle of 90° to achieve a mass balance of the crankshaft drive, which is optimised for
low vibration and increased comfort. For reasons of stiffness and due to the high loads resulting from combustion pressure, engine speed and vibrations, a bedplate design has been chosen for the crankcase, the first-ever application in a production V engine by BMW. For an optimum alignment of the crankshaft, grey-cast iron inserts have been integrated into the aluminium bedplate, which also serve to enhance acoustics, increase vibrational comfort and ensure a high oil supply rate. The extremely stiff crankshaft is supported by six bearings.

High-pressure bi-VANOS and individual throttle butterflies.

The bi-VANOS variable valve timing featured in the new M5 engine ensures
an optimum charge cycle, thus helping to achieve extremely short adjustment times. This means in practice: increased performance, an improved torque curve, optimum responsiveness, lower consumption and fewer emissions. Each cylinder has its own throttle, a feature typical of
racing cars. Throttle control is fully electronic and cylinder bank specific.
Dual exhaust system made of stainless steel.

The exhaust system is made of seamless stainless steel and has a dual-flow design all the way to the silencers. The exhaust gases finally leave the system through four tailpipes which are what make the rear end of the M vehicles so unmistakable. The exhaust system complies with the European EU4 and the US LEV2 emission standards.

The engine control module: the first of its kind in the world.

The MS S65 engine management system is the central factor behind the V10’s outstanding performance and emission data. This engine management system is unparalleled in its package density. Its processors are the most powerful ones which are currently approved for use in automobiles, as high engine speeds and comprehensive management and control tasks demand the utmost from this system.

Highlight in engine management: ionic current technology.

The ionic current technology featured by the engine management unit is
a technological highlight which serves to detect engine knock, misfiring and combustion misses. Utilising the spark plug in each cylinder, this system
helps to pinpoint engine knock, to check for correct ignition and to detect any ignition misses. Thus, the spark plug has a dual function – as an actuator for the ignition and as a sensor for monitoring the combustion process.

Seven-speed SMG gearbox conveys M power to the tarmac.

The high-revving concept only succeeds in combination with a gearbox
which translates the torque available to the engine, by means of a short overall transmission ratio, into optimised forward thrust.
The seven-speed SMG gearbox is precisely the right transmission to ideally convey the V10 engine’s power via the drive train to the wheels. BMW M is the first manufacturer worldwide to offer a seven-speed sequential gearbox
with drivelogic function. Even more highly perfected than the previous six-speed transmission, the seven-speed SMG gearbox enables manual gear selection with ultra-short shifting times as well as comfortable cruising thanks to automated gear selection. The purpose of the additional seventh gear is to reduce engine speed and torque gaps.

New SMG gearbox’s speed up by 20 percent.

With the seven-speed SMG gearbox, gears can be changed using the gearshift lever on the centre console or the paddles on the steering wheel. Compared to the previous SMG transmission, changing gears is 20 percent faster with the new SMG generation. Never before has it been quicker to change gears with a transmission of this kind. The advantage for the M5 driver: Gear change is smooth and accomplished at a speed impossible to
reach even by the most proficient driver, thus making the inevitable power flow interruptions when changing gears hardly noticeable. The M5 delivers
an almost jerk-free performance when accelerating from a standstill to its top speed.

Drivelogic: the driver determines the SMG’s characteristics for changing gears.

Thanks to the SMG’s drivelogic function, the driver can choose from eleven gear change options, which enable him to adapt the SMG’s characteristics to his very own style of motoring.

Six of these programs can be pre-selected in the sequential manual
gearbox mode (S mode), the spectrum ranging from balanced dynamic to very sporty. With the gearbox in the S mode, the driver always shifts gears manually. Whenever the driver activates the Launch Control function, the SMG Drivelogic shifts gears shortly before the maximum engine speed is reached at precisely the right moment and with optimum slip until the M5 reaches its top speed.

In the Drive (D mode) automatic gearshift mode, the transmission shifts
the seven gears automatically, depending on the program selected,
the driving situation, the road speed and the position of the accelerator pedal.

SMG for increased safety and comfort.

The seven-speed SMG gearbox not only supports the driver in achieving motor sports performance, but also offers scores of safety features. In critical situations, when the driver shifts down on a slippery surface, for example, the gearbox opens the clutch in the fraction of a second in order to prevent the M5 from swerving out of control in the event of excessive drag torque at the driven wheels. Further functions are the climbing, which prevents the car from rolling backwards during hill starts as well as the hill detection, which adjusts the shift points on gradients and descents. This prevents gear hunting when going uphill. When driving downhill, the hill detection holds the lower gears for longer in order to make effective use of the engine’s braking power.

Maximum driving pleasure.

The interaction of the V10 engine and the seven-speed SMG gearbox results in a level of performance, which has so far been inconceivable for series-production saloons. Above all, there is one thing the M5 gives to its driver: driving pleasure at its best. Compared to the previous M5, the current model comes up trumps in all performance and fun disciplines: it accomplishes the 0 to 62 mph sprint in less than five seconds and reaches the 200 km/h (124 mph) mark after a mere 15 seconds to go on to the electronically limited top speed of 250 km/h (155 mph). A glance at the speedometer reveals where this power package would head for if maximum speed was not electronically limited: an awe-inspiring 330 km/h (205 mph).

The Nürburgring serves as a test track.

Compared to all direct competitors, the interaction of actual forward thrust and a low vehicle weight is a strong argument in favour of the new M5. Also in this respect, the M5 sets the benchmark and leaves its competitors far behind.

An undisputed gauge of driving dynamics is the northern loop of the legendary Nürburgring race track. For decades, the world’s most demanding race track has been the perfect place of separating the wheat from the chaff. There is no other place where the interaction of vehicle components when taken to the limits can be observed as well as on the Nürburgring’s northern loop. With lap times of approximately eight minutes, the M5 can hold its own and is a worthy competitor of thoroughbred sports cars, leaving its competitors far behind. By the way: traditionally, all M vehicles are tested there.

M suspension based on the 5 Series: the icing on the cake.

The aforementioned lap time demonstrates that the M5 can be extremely sporty. Although the suspension of the basic 5 Series model is undoubtedly very good, such a record performance with respect to dynamics would
not be possible. This is why the M5 is also totally unique with regard to its suspension.

Many detail solutions and changes turn the 5 Series into an M5.
Consequently, the suspension and its electronic assistants have been either exclusively developed for the new M5, undergone extensive modifications or adapted to the special M performance. For example, the M5’s running gear is by no means a lowered 5 Series suspension. Instead, it is an optimised design created from scratch. The suspension assisting systems, some of which have the same name as those of the 5 Series, have been optimised for this vehicle. On the one hand, this suspension contributes greatly to the M5 being the technological culmination of the successful BMW 5 Series. On the other hand, it clearly demonstrates that the M5 is a unique model with a distinctive appearance.

Variable M differential lock.

The M5 has a variable, torque-sensing differential lock bestowing the vehicle with a high level of driving stability and optimum traction, above all when accelerating out of bends. Even in extremely demanding driving situations, i.e. when there are major differences in the coefficients of friction at the driven wheels, it offers a decisive advantage in terms of traction. A further advantage is that it instantly builds up an increasing locking power if the speed difference between the driven wheels rises, thus guaranteeing optimum forward progress at all times.

Only featured in the M5: DSC with two selectable driving dynamics programs.

A new generation of the Dynamic Stability Control (DSC) has been especially developed for the M5. The DSC system can be deactivated by pressing a button on the selector lever cover. The driving dynamics programs are pre-selected in the so-called MDrive and can be called up using the MDrive button on the steering wheel. Whilst the first DSC mode by and large corresponds to that of the 5 Series, the second mode – the M Dynamic Mode – is highly appreciated by sports-minded drivers.
EDC: the spectrum ranges from sportingly firm to comfortable.
The M5’s Electronic Damper Control (EDC) enables the driver to choose from three programs (comfort, normal and sport), thereby adjusting the suspension characteristics accordingly. The driver can operate the EDC function via the MDrive button on the steering wheel or the push button next to the SMG selector lever.

Power button activates engine characteristics “on demand”.

The driver often does not need the M5’s full performance and maximum agility, for example in city traffic. This is why the markedly comfortable
P400 performance program with an engine output of 400 bhp is automatically activated whenever the engine is started. At the push of a button (the so-called Power button on the selector lever cover), the ten-cylinder powerplant’s full power is at the driver’s disposal. The accelerator pedal kinematics adopt spontaneous characteristics, giving free rein, in the P500 program, to the sporty driver and eliciting, in the P500 sport program, uncompromising racing pleasure.

High-performance brakes derived from motor sport.

To complement its immense power output, the M5 is equipped with a generously sized high-performance braking system with perforated, weight-optimised compound brake discs. The aluminium twin-piston sliding
callipers (analogous to the BMW 7 Series), which have been optimised for minimum weight and maximum stiffness, help the M5 to achieve stopping distances similar to those of red-blooded sports cars: deceleration from
62 mph to 0 is accomplished in under 36 metres, the braking distance from 124 mph to a standstill is less than 140 metres.

The high-performance business express.

A wolf in sheep’s clothing – this description would fit if the basic 5 Series, and particularly the new M5, looked “tame” when viewed from outside. In fact, the 5 Series already looks sporty, elegant and athletic. It is no coincidence that this 5 Series represents BMW’s dynamic business class. The M5 is set apart from the basic model by a host of striking and hidden details, which further add to its powerful, sporty and dynamic looks. An athlete in business attire would be an apt description of the new M5.
Exterior with understatement.

The differences in design versus the basic 5 Series are discreet but consistent, giving the M5 a surprisingly high level of uniqueness in terms of looks, without questioning the common genes with the BMW model series. The modified front and rear aprons are instant eye catchers. Another difference is the modified side sills and the somewhat more prominent wheel arches. Traditionally, the M differs from the “normal” BMW in its
exclusive exterior mirror design, the four tailpipes, which have also become an unmistakable feature of all M vehicles, and the exclusive wheel design.
For the first time, the M5 sports very attractive gills which are incorporated into the front side panel.

An even sportier interior.

The M5 comes with a leather interior in three different colours, which makes it look even more sophisticated than the lavishly equipped basic model or – for an extra price – with a full leather interior, which looks absolutely stunning. Further important differences versus the 5 Series are the instrument cluster, the optional M-specific head-up display, the steering wheel with MDrive buttons and the redesigned centre console.
Business express for everyday use.

All vehicles made by BMW M GmbH are very convenient for everyday motoring. This particularly applies to the M5: despite its awe-inspiring performance which is reminiscent of that of a racing car, it has remained an elegant and comfortable saloon perfectly suitable for longer journeys, an integral characteristic of BMW 5 Series cars. Thus, one can say that the M5’s racing ambitions neither impair driving comfort, active and passive safety, nor do they reduce the space available for passengers and luggage. Even in terms of consumption and environmental compatibility, the M5 is a real paragon – just like all BMW automobiles.

Press Release Part 2: The new V10 engine in the BMW M5: A masterpiece in engine construction.(Long version)

The heart of every BMW is its powerful engine. It is more than obvious that this particularly applies to the models made by BMW M GmbH.

This description alone, however, would not do justice to the new engine in the M5: modestly put, this ten-cylinder power unit is a milestone in modern
engine construction. It is one of the most fascinating engines the world over ever to be used in a series-production vehicle.

Some automobile aficionados also attach great importance to the sound of
the engine. This is also the case with the V10: this technological masterpiece is to the sports vehicle aficionado what a symphony is to the ears of music lovers. Similarities to the sound of the BMW WilliamsF1 racing engine won’t go unnoticed. The M5’s V10 engine not only has got the same number of cylinders as its Formula 1 counterpart. Both engines also have the high-revving concept in common, a principle which generates enormous forward thrust from high engine speeds and is a characteristic of all high-performance, naturally aspirated BMW M GmbH engines. All this, in conjunction with the ten cylinders, results in an orchestra-like staccato, something that is normally only heard on the race track.
First high-revving V10 engine to be featured in
a regular-production saloon.

The new M5’s high-revving V10, which has so far been reserved for racing cars and exotic low-volume cars, is the first engine of its kind to be used in a series-production saloon. In order to do justice to the exclusivity of the M family, this high-performance power unit offers a performance which is truly impressive: it has ten cylinders, displaces five litres and produces a
maximum output of 507 bhp and a maximum torque of 520 Newton metres. Engine speed peaks at 8,250 rpm – a road-going athlete par excellence.
But there is more to the engine than just impressive performance data.
At the slightest movement of the gas pedal, the high-revving normally aspirated engine reveals itself to be a typical sports engine. At the same time, it is perfectly suited for use in daily traffic. The M5 is a saloon for everyday use with the heart of an athlete – in other words, a roadworthy sports saloon. The M5 fully lives up to these two demands, opening up a new dimension of effortlessness. 20 years after the presentation of the first M5 marked the introduction of the segment of powerful sports saloons, this new engine once again points the way forward in this particular class.

Inspired by the Formula 1 engine.

The engine was redesigned from scratch by the BMW M GmbH engineers. When constructing the power unit, the engineers drew inspiration
from the BMW WilliamsF1 engine, which is generally regarded as the most powerful engine on the starting grid of the top echelon of motor sport.
On the other hand, they transferred all M specific features from series-production automobiles, such as bi-VANOS, individual throttle butterflies and the most powerful engine electronics system currently available, an in-house development, as well as a traverse force regulated oil supply system.

In order to create a worthy successor of the previous M5, which features a 400 bhp V8 engine, it was essential to do one thing: to increase performance even further. In engine construction there are three possibilities for boosting performance: increase the cubic capacity and raise maximum torque in the process, boost performance by using a turbocharger or a compressor or use a high-revving concept to increase torque.
Power is more than increased horsepower.

There is more to it than pure output. Acceleration behaviour and driving dynamics are further important aspects, which are greatly dependent on the actual forward thrust and the vehicle weight. The forward thrust at the
driven wheels is a result of both torque and the total ratio. The high-revving concept contributes greatly to an optimum transmission and rear-axle ratio, which, in turn, helps to unleash impressive drive forces.
When it comes to the laws of physics, the wheat is separated from the chaff, even if the engines under comparison are identical in output. If an engine’s cubic capacity is increased, one has to put up with – for the benefit of high performance and torque – the problem of additional weight, more space required and higher fuel consumption. Supercharged engines also have drawbacks. Only rarely do they excel due to fuel economy and their spontaneity, i.e. the engine’s ultra-fast response to the driver’s inputs, fails to meet the high demands made of an M overall concept.
High-revving concept is the perfect solution.

The third option, a compact, high-revving naturally aspirated engine,
is the perfect answer. If only for the sake of tradition, for the BMW M engineers the following solution was the ideal choice: boosting performance by increasing torque. In this context it must be said that, from a technological viewpoint, the high-revving concept is far more sophisticated, so that it is much more difficult to put this concept into practice. After all, it is no coincidence that BMW’s introduction of the new M5 has made them the first manufacturer worldwide to position a high-rpm V10 engine in the segment of powerful final production sports saloons.

Offering a maximum speed of 8,250 rpm, the ten-cylinder engine has ventured into terrain which has up to now been reserved for thoroughbred racing cars. By way of comparison: the previous M5’s engine speed is electronically limited to 7,000 rpm. The new ten-cylinder powerplant has broken the 8,000 rpm barrier.

Formula 1 technology takes to the roads.

With this new engine beneath the bonnet, the M5 redefines what is technologically feasible in the manufacture of series-production engines.
The higher the torque, the closer the engine gets to the physical limits.
The following comparison gives you an idea of the immense stress acting on the material: at 8,000 crankshaft revolutions per minute, each of the
ten pistons covers a distance of approximately 20 metres per second. Coming back to the ten-cylinder engine in the BMW WilliamsF1: at 18,000 rpm, the pistons move as much as 25 metres per second. The difference is, however, that a Formula 1 racing engine only has to travel 800 kilometres in one racing weekend, whilst the M engine must last the lifetime of the
vehicle, regardless of the climate, traffic situation and style of motoring.
It is evident that the M5 engine has various basic technological principles, production methods and materials in common with the Formula 1 engine and that it is based on technological transfer.

A 25 percent plus in performance – a new dimension
of driving dynamics.

The completely redesigned V10 engine, a high-revving ten-cylinder powerplant, is superior to its predecessor, which features 8 cylinders and the same cubic capacity, in all disciplines. Proof of this is provided by its performance which is up by more than 25 percent. The new V10 engine produces a maximum output of 507 bhp (373 kW) at 7,750 rpm (maximum output of the V8 is 400 bhp – 294 kW – at 6,600 rpm). Weighing in at just
240 kilograms, the new ten-cylinder engine is almost identical in weight with its eight-cylinder forebear. Given its awe-inspiring performance, the new ten-cylinder engine is a real lightweight. However, the engine is a heavyweight when it comes to its output per litre: the ten-cylinder M5 exceeds the magical mark of 100 bhp per litre of cubic capacity, its specific output being on par with that of racing cars.

Engine speed has a major influence on performance and torque.

As far as maximum torque (520 Newton metres) is concerned, the ten-cylinder matches the eight-cylinder power unit. Nevertheless, the new M5 beats its predecessor in all disciplines relating to driving dynamics. This phenomenon is also connected to the engine speed. A case in point: if a cyclist changes down when going uphill, he must pedal faster but he will master almost every gradient no matter how steep. If he does not change gears or if he even changes up, he needs a lot more energy or he has to get off the bike.

If there are two cyclists with the same amount of stamina, it is always the cyclist who pedals faster that wins the race.

The logical consequence is that the new M5 with its high-revving engine also effortlessly outdoes all direct competitors who exclusively rely on the
“torque concept” of an eight-cylinder engine with an increased cubic capacity. In addition, this engine’s superiority can be put down to the fact that the concept-related extremely high torque of competing engines has to be transferred via a massively reinforced and heavy drive train – added weight and mass that must also be accelerated. Thanks to the V10’s high-revving concept, a considerably lighter drive train can be used and closer gear ratios can be achieved.

By the way, the new M5 also outdoes its competition when it comes to
torque: peak torque of 520 Newton metres is reached at 6,100 rpm, a torque of 450 Newton metres is already obtained at 3,500 rpm. And 80 percent of maximum torque is available at up to 5,500 rpm, which is a wide speed range for an engine of this calibre.

Ten cylinders – the sports engine concept.

Its dimensions, number of components and filling quantities make the ten-cylinder engine the perfect choice for a high-performance sports powerplant. The new V10 therefore represents the perfect solution for a car such as the M5. In addition, the ten cylinders with a displacement of 500 cc each, fully live up to the ideals of the most discerning engineers.
Compact design for increased robustness and comfort.

BMW, one of the leaders in engine construction, has made a name for itself primarily as a manufacturer of inline engines. When constructing the new ten-cylinder engine, the engineers arranged the two five-cylinder banks at an angle of 90° (V-configuration) with a 17 mm offset to create a compact aggregate. The 90° angle has been chosen due to its low-vibration and comfort-oriented mass balancing properties. In its geometry the engine solves the conflict between minimum vibrations and maximum component robustness.

The cylinder crankcases are cast utilising the low-pressure gravity die casting method and are made of hypereutectic aluminium-silicon alloy. This special alloy contains at least 17 percent silicon. The cylinder liners are created by precipitation of the hard silicon crystals. Additional liners are not necessary – the iron-coated pistons run up and down in the uncoated bores. Stroke is 75.2 mm, bore is 92 mm, overall cubic capacity amounts to 4,999 cc.

By the way, the blocks for the M5 engines are cast at the same place as the Formula 1 engines: at the BMW light alloy foundry in Landshut.
Bedplate derived from racing technology.

High engine speeds, high combustion pressures and high temperatures put an enormous strain on the crankcase. Therefore the engineers have chosen the so-called bedplate design, a compact and extremely stiff configuration which is derived from car racing. The new engine in the BMW M5 is the first series-production V engine to feature such a bedplate design. The aluminium bedplate with integral grey-cast iron inserts ensures high-precision crankshaft alignment, keeping the main bearing clearance over the entire operating temperature range at a minimum. The grey-cast iron inserts help to reduce the thermal expansion of the aluminium casing. To ensure positive coupling with the adjoining aluminium frame, the inserts have been provided with openings. At the same time, this architecture contributes to fulfilling the demands made of the M5’s engine acoustics.
The extremely stiff and finely balanced crankshaft made of forged, high-
tensile steel is supported by six bearings and weighs a mere 21.8 kilograms.
It balances inertia forces and is designed for maximum torsional stiffness.
The main bearing diameter measures 60 mm at a bearing width of 28.2 mm. Two conrods connect to each of the five crank pins, which are offset at an angle of 72 degrees. A reduced cylinder spacing of only 98 mm enables the use of a short crankshaft, thus resulting in high flexural strength and torsional stiffness, as well as a very low weight.

Every gram counts in lightweight construction.

The weight-optimised pistons are made of high temperature resistant aluminium alloy and are provided with an iron coating. They weigh a mere
481.7 grams, including piston pins and rings. The compression height is 27.4 mm at a compression ratio of 12.0:1. The pistons are cooled using oil spray jets which are directly connected to the main oil duct. The 140.7 millimetres long, weight-optimised, fracture-split trapezoidal connecting rods are also made of high-strength steel and effectively reduce the oscillating masses. Each of the connecting rods forged from 70MnVS4 has a weight of only 623 grams, including the bearing shells.
The single-piece aluminium cylinder heads of the V10 engine are also produced at the BMW light alloy foundry in Landshut. The cylinder heads feature integrated air ducts for air injection which is important for rapid catalytic converter warm-up. The cylinder heads incorporate four valves per cylinder, a BMW specific engine architecture. The valves are actuated by spherical tappets featuring hydraulic valve play compensation. The tappet diameter has been reduced to 28 millimetres and its weight is down to 31 grams.

Through optimisation of all parts and components of the valve train, the moving mass has been reduced by 17.5 percent in comparison with
the predecessor model. The diameter of the intake valve is 35 millimetres,
the exhaust valve measures 30.5 millimetres in diameter.
Innovations with attention to the smallest detail reduce
maintenance costs.

The intake valves are exclusively manufactured for the M5 engine.
With a reduced shaft measuring only 5 mm in diameter, there is hardly any impedance of the flow in the intake tract. Hydraulic valve play compensation units automatically provide for the optimum valve adjustment at all times, which is beneficial to the customer as it lowers maintenance costs.

The higher the engine output, the higher the need for cooling the engine, particularly in the vicinity of the combustion chamber. Compared to conventional systems, the cross flow cooling concept of the M5 engine considerably minimises pressure losses in the cooling system. It ensures
an even temperature distribution in the cylinder head and the reduction of peak temperatures in critical areas of the cylinder head. Every single
cylinder is evenly supplied with the optimum amount of coolant which flows from the crankcase at the outlet side through the cylinder head
and via the manifold strip at the intake side to the thermostat or cooler.
High-pressure bi-VANOS for an optimum charge cycle.

The bi-VANOS variable camshaft control, which celebrated its world
premiere in the M3 back in 1995 and has been further optimised for use in the current M3 model, is also featured in the new M5 engine. It ensures an optimum charge cycle, thus helping to achieve extremely short adjustment times. This means in practice: increased performance, an improved torque curve, optimum responsiveness, lower consumption and fewer emissions.
For example, at the lower end of the load and engine-speed scale the car can be driven with an increased valve overlap, boosting internal exhaust gas recirculation. This, in turn, leads to a reduction in charge cycle losses and fuel consumption.

The adjustment of the angles as a function of the accelerator pedal position and the engine speed is infinite and map-controlled. For this purpose, the sprocket, which connects to the crankshaft via a simplex chain, is linked to the camshaft via a two-speed, helical gearbox. In the event of an axial displacement of the adjusting piston, the helical set of teeth turns the cam relative to the sprocket, which allows for the variation of the angle of the intake camshaft by up to 66° and that of the outlet camshaft by a maximum of 37° in relation to the crankshaft.

The M bi-VANOS technology requires very high oil pressures for ultra-precise, high-speed camshaft adjustment. This is why a radial piston pump in the crank chamber increases engine oil pressure to an operating pressure of 80 bar.

The map-controlled high-pressure adjustment ensures reduced adjustment times, allowing for the optimum angle, precisely the right ignition point and injection quantity under all conditions and in accordance with load and engine speed.

Constant lubrication even in hard cornering situations.

Four oil pumps provide the engine with lubricating oil. The reason behind this unusually elaborate oil supply system is the M5’s exceptional driving dynamics with extreme acceleration rates. The sports saloon has a cornering capability of over 1 g. During extreme cornering centrifugal forces force the engine oil to the cylinder bank facing the outside of the bend, thereby preventing the natural return of oil from the cylinder head, which might lead to inadequate oil supply in the oil sump. Should the worst come to the worst, the oil pump sucks air. In order to reliably prevent this situation, the engine features a traverse force regulated oil supply system. This system incorporates two electrically-operated duo-centric pumps which pick up oil from the outer cylinder head and transport it to the main oil sump if lateral acceleration rates exceed 0.6 g. A lateral-g sensor transmits signals to the pumps. The oil pump itself is a continuously variable pump with volume control which delivers exactly the amount of engine oil needed by the engine. This is achieved by the variable eccentricity of the pump’s rotor in relation to the pump casing, depending on the oil pressure in the main oil duct.

Proper oil circulation in all conditions.

In extreme braking manoeuvres the M5 might even reach negative acceleration rates of up to 1.3 g. If deceleration rates are that high, it might well be that the amount of oil flowing back to the oil sump, which functions as an intermediate buffer, is not sufficient, particularly since the oil sump is located behind the front-axle support in order to save space. The worst-case scenario is that lubrication is interrupted. In order to prevent this situation, the M5 engine has been fitted with a so-called “quasi-dry sump oil system” which incorporates two oil sumps: a smaller one in front of the crossmember and a bigger one behind. A recirculating pump has been integrated into the housing of the oil pressure pump, which picks up oil from the small front oil sump to convey it to the big rear oil sump, which has been carefully shielded. The return passages and the pickup point of the oil pressure pump are perfectly tuned to ensure proper oil circulation in all conditions.

Ten individual throttle valves are electronically actuated.

Each of the ten cylinders has its own throttle valve, each cylinder bank, in turn, is served by its own actuator, a concept we are familiar with from motor sport. Although this system is very complex from a mechanical viewpoint, there is no better way to achieve spontaneous engine response. In order to attain maximum engine responsiveness in the lower speed range, and to achieve an immediate vehicle response at the high end of the performance spectrum, all throttle valves are controlled fully electronically. Two contactless Hall potentiometers determine and evaluate the position of the accelerator pedal 200 times per second. The engine management reacts to changes and causes the two actuators to adjust the ten throttle valves. It goes without saying that this process is performed at a lightning-fast speed: it takes just 120 milliseconds to completely open the throttle valves, this is about the time an experienced driver needs to fully depress the accelerator pedal.

This gives the driver a feeling of instantaneous response and allows him to “dose” the gas pedal even more precisely. At the same time, the electronic throttle valve actuation keeps transitions from overrun to part load and vice versa smooth and harmonious.

The V10 engine uses ten flow-optimised intake trumpets to “breathe in”
air from two intake plenums. The intake plenums and the trumpets are made of a lightweight compound material that contains 30 percent fibreglass.

Dual exhaust system made of stainless steel.

Although the intake system contributes considerably to the remarkable performance of the new M5 engine, the importance of the exhaust system must not be underestimated. Also with respect to the exhaust system,
only the best was good enough for the BMW M engineers. The two stainless steel 5-in-1 high-performance tubular headers have been optimised for equal length by using complicated calculating methods. For exact pipe diameters, the seamless stainless steel pipes are formed from the inside using an interior high-pressure forming technique (hydroforming) with a pressure of up to 800 bar. The manifold pipes have a wall thickness of just about 0.8 mm, which is also a sign of the M engineers’ incredible attention to detail when designing this masterpiece in engine construction.
Even a sports engine can be a paragon of cleanliness.

When designing the exhaust system, the engineers considered it most important to keep the counterpressure to a minimum and to optimise the gas-dynamic design for impeccable performance and torque behaviour.
The exhaust system has a dual-flow design all the way to the silencers.
The exhaust gases finally leave the system through four tailpipes which are what make the rear end of the M vehicles so unmistakable.

As you would expect from a BMW M automobile, two trimetal-coated catalytic converters per exhaust line clean the exhaust gases produced by the ten-cylinder engine in compliance with the demanding European EU4 standard and the American LEV 2 standard. There are two underfloor catalysts. The other two catalytic converters (one for each exhaust line) are located close to the engine.

In conjunction with the thin-walled exhaust manifolds, these catalysts quickly reach their optimum operating temperature, which means that they are fully operational quickly after a cold start. They excel due to their low pressure losses and high mechanical strength.

The engine control module: the first of its kind in the world.

The MS S65 engine management system is the central factor behind the V10’s outstanding performance and emission data. It enables the optimum coordination of all engine functions with the different vehicle control units, especially with that of the SMG. This innovative control unit is a world-first in a regular-production car: with more than 1,000 individual components, this engine management system is unparalleled in its package density. By the way, hardware, software and functioning are BMW M in-house developments.

High engine speeds call for high-level performance.

Due to the M5 engine’s high speeds and the large number of control and regulating tasks, the demands placed on the MS S65 control unit’s performance are extremely high. In order to meet these demands, the engine control module has been equipped with three 32-bit processors that perform more than 200 million individual calculations per second. Compared to the M3 control unit presented only four years ago, this represents a performance increase by factor eight. In terms of memory capacity, the latest control unit outdoes the previous one by as much as factor ten. Receiving more than 50 input signals, this system calculates for each individual cylinder and for each individual cycle the optimum ignition point, the ideal cylinder charge, the injection quantity and the injection point. At the same time this system calculates and makes the necessary adjustments for the optimum camshaft angle and the optimum position of the ten individual throttle butterflies.

By pressing the power button on the selector lever cover, the driver can activate a sportier program with full performance characteristics. The activation of this program results in a more progressive response of the throttle butterfly to the accelerator pedal with the dynamic transient functions of the electronic engine management system switching over to a more instantaneous response. In the M5, the more comfortable of the two settings is automatically applied as soon as the engine is restarted. The change-over can also be pre-configured and called up in MDrive. In MDrive, there is a further, very sporty program available.

Comprehensive ancillary tasks for the engine management system.

The electronic throttle valve control is based on a so-called power and torque structure which uses a potentiometer on the accelerator pedal to measure the driver’s wish for power and performance and converts this to the desired function. The power and torque manager adjusts this request function by adding the power signals from the auxiliary engine units, such as the conditioning compressor or the generator. Functions such as idle-speed control, emission control and knock control are also coordinated and aligned to the maximum and minimum output and torque curves permitted by the Dynamic Stability Control (DSC) and the Engine Drag Force Control (EDFC).

The target output and torque calculated in this way is then maintained at the desired level, while taking into account the current ignition angle. In addition, the engine management system carries out comprehensive tasks for onboard diagnosis with various diagnosis routines to be used by the workshops as well as other functions, and the control of peripheral aggregates.

Highlight in engine management: ionic current technology.

The ionic current technology featured by the engine management unit is
a technological highlight which serves to detect engine knock, misfiring and combustion misses. The uncontrolled ignition of the fuel in the cylinder is called engine knock. In order to prevent engine knock, engines without knock control generally feature a lower compression ratio. Furthermore, the ignition point is retarded to prevent the cylinders from reaching or even exceeding the knock limit, which might cause damage to the engine. The “safety distance” to the knock limit resulting from this measure always has an adverse effect on fuel economy, engine output and torque. Active knock control, however, is an efficiency-boosting measure as it ensures optimum ignition timing and protects the engine from damages at the points of operation that are prone to knock.

Conventional systems employ several detectors on the outside of the cylinder to send knock signals to the knock control. In BMW M vehicles, one sensor monitors two cylinders. As the BMW M ten-cylinder engine is based on a multi-cylinder and high-revving concept, the use of those detectors alone is not sufficient in order to reliably detect engine knock. Due to the high engine speeds, evaluation must be very precise for optimum combustion quality in the cylinders, a factor which strongly influences the components’ durability as well as the emission behaviour. This is where ionic current measurement comes into play.

The spark plug takes on additional control functions.

This technology utilises the spark plug in each cylinder to sense and control engine knock. It also helps to check for correct ignition and to identify possible ignition misses. Thus the spark plug has a dual function – as an actuator for the ignition and as a sensor for monitoring the combustion process. Here again, the difference to conventional knock and ignition sensors becomes evident: they are located outside the combustion chamber, whilst the ionic current measuring is done inside the combustion chamber as spark plug and sensor are combined into one.
Measurement in the heart of the combustion chamber.

Temperatures in a spark-ignition internal combustion engine’s combustion chamber can reach up to 2,500 degrees. These high temperatures and
the chemical reactions produced during combustion activity lead to a partial ionisation of the fuel-air mixture in the combustion chamber. Particularly in the flame front, the gas becomes conductive through the generation of ions by means of separation or accumulation of electrons (ionisation). The spark plug electrode, which is electrically isolated from the cylinder head and linked to a small control unit operating independently from the engine management system, the so-called ionic current satellite, is supplied with a DC voltage and measures the so-called ionic current between the electrodes, the measured value depending on the degree of ionisation of the gas flowing between the electrodes. The ionic current measurement technique retrieves information on the combustion process directly from where things are happening, the combustion chamber. The ionic current satellite receives signals from the five spark plugs assigned to each cylinder bank, amplifies them and sends the data to the engine management system for analysis, which then makes the necessary interventions (for each cylinder separately). For example, cylinder engine knock and the ignition point are adjusted for each single cylinder in order to optimise the combustion process. The spark plug, which is both an ignition source and a sensor, facilitates diagnosis when performing service and maintenance.

Press Release Part 3: The new sequential M transmission: Shifting gears even faster with the seven-speed SMG gearbox.

The new sequential M transmission: Shifting gears even faster with
the seven-speed SMG gearbox.

The concept of a high-revving engine only proves successful if the engine is combined with a transmission that matches the prodigious performance
and translates the torque made available by the engine into optimum forward thrust by means of a short overall transmission ratio.

The seven-speed sequential M gearbox (SMG) is exactly what is needed
to ideally transfer the power of the V10 engine to the drive train and finally to the wheels. With this gearbox, BMW M is the one and only manufacturer world-wide to market a seven-speed sequential gearbox with drivelogic function. Nonetheless, the new seven-speed gearbox is by no means an extended six-speed transmission. Instead, it is a completely novel gearbox, which has been designed exclusively for use in the new M5. Even more
highly perfected than the previous six-speed transmission, the seven-speed
SMG gearbox enables extremely fast manual gear changes as well as comfortable cruising thanks to the automated gearshift mode.

The new transmission is technically designed to handle a torque of up to
550 Newton metres and engine speeds of up to 8,500 rpm. This gives
the transmission sufficient reserves to ensure reliable operation throughout the new M5’s entire lifecycle, which is further further enhanced by a separate oil cooling system for the high-performance engine

Even closer speed gaps than with the six-speed gearbox.

Compared to a six-speed gearbox, seven gear steps offer even more reduced engine speed and torque gaps when changing gears. As forward thrust is closely related to high engine speeds, these reduced gaps assist the new M5 in achieving awesome acceleration.

The SMG transmission stands for sublime shifting pleasure.

It goes without saying that the new seven-speed SMG gearbox offers all the advantages inherent in a sequential gearbox concept: gears are changed using the gearshift lever on the centre console or the paddles on the steering wheel. The driver does not have to press down the clutch and gear changes are possible even with the throttle foot flat on the floor. As opposed to an automatic transmission, the SMG transmission does not require an energy-consuming and performance-impairing torque converter.


As a matter of principle, all gears of the SMG transmission are shifted electro-hydraulically. The SMG gearbox features shift-by-wire technology, which has its origins in aerospace synergism and by which gears are changed in the fraction of a second without a mechanical link. In contrast to previous six-speed SMG transmission, the new M5’s SMG hydraulic unit and the actuators have been integrated into the transmission housing. If a gear change request is made, the control unit actuates the respective magnetic valves which control the overall system’s hydraulics. As a next step, the hydraulic oil with a high operating pressure of up to 90 bar flows swiftly via a magnetic valve into the clutch master cylinder to open the clutch. Then, using solenoid valves in the hydraulic unit, four hydraulic cylinders in the actuator are switched, which carry out the actual shifting process by means of four separate gearshift rods. When shifting down, the engine double-declutches automatically.

The new SMG boosts speed by 20 percent.

The previous second-generation SMG transmission was already rapid-shifting, and, to top it all, the new, third SMG generation accelerates the process of shifting gears by another 20 percent: for a gearbox of this kind, the shift speed is unrivalled and the advantages for the M5 driver are as follows: gear changes are extremely smooth and effected at a speed even the most experienced driver could not attain, thus making the inevitable power flow interruptions when changing gears hardly noticeable. The M5 delivers an almost jerk-free performance when accelerating from a standstill to its top speed. The driver gets much enjoyment out of shifting gears as SMG elicits a true “Formula 1 feeling”.

Changing gears with an SMG gearbox also makes a valuable contribution to traffic safety: as shifting always involves the same level of speed and
precision and is therefore absolutely reproducible, the driver does not have to concentrate that much on the process, meaning that the SMG gearbox promotes precise, safe and relaxed driving.

Drivelogic: the driver determines the SMG’s gear change characteristics.

Thanks to the SMG’s drivelogic function, the driver can choose from eleven gear change options, which enable him to adapt the SMG’s characteristics to his very own style of motoring. These programs differ from each other in the pre-selected gear change time: the higher the selected program, the engine speed and torque, the shorter the shift times.

Six of the eleven gear shift options can be pre-selected in the sequential manual gearbox mode (S mode), the spectrum ranging from balanced dynamic to very sporty. With the gearbox in the S mode, the driver always shifts gears manually, and the transmission does not at any time intervene in the shifting process.

Launch Control: moving up to maximum speed with full performance.

With the gearbox in S mode, the driver can profit from the Launch Control function, which is a complement to the purist, sporty S6 driving program.
The Launch Control function enables “rookie racing drivers” to make a perfect standing start in order to maximise the initial acceleration. This function requires the prior deactivation of DSC.

The aim of the Launch Control function is to relieve the driver of shifting gears, giving him more freedom to concentrate on his actual job of driving. When the car is stationary, the only thing the driver has to do is to flip the selector lever forward and keep it in that position. If he now fully depresses the accelerator pedal, the engine is automatically set to its optimum starting speed. If the driver releases the selector lever, the M5 is accelerated with the ideal amount of slip, provided the driver keeps the accelerator pedal fully depressed. The driver does not have to change gears until the M5 reaches its peak speed – the SMG gearbox with drivelogic automatically shifts through the seven gears and changes from one gear to the next gear shortly before maximum engine speed is attained.
As is the case with all driving programs, a telltale in the cockpit informs the driver of the gear currently in mesh.

Automatic gearbox – one that can hold its own even on the race track.

Five of the eleven gear shift options of the Drivelogic function are available in the so-called automated D mode. If this mode is activated, gears are changed automatically, depending on the driving program selected, the driving situation, the speed and the position of the accelerator pedal. With the D1 driving program selected, for example, the gearbox sets off in second gear and ensures particularly delicate and smooth engagement of the clutch, this being of great help in wintry conditions.

Although having opted for automatic gearchanging, the driver can influence the process by, for example, releasing the accelerator pedal slowly, thus determining, also in D mode, the time when the gearbox shifts up. In turn, by depressing the accelerator pedal all the way down to the floor, he is able to effect fast downchanges. In S as well as in D mode, the gearbox automatically shifts down to the first gear as soon as the car is slowed to a halt. All the driver has to do to set the car in motion again is to step on the gas pedal.

Special functions for increased safety and comfort.

The seven-speed SMG gearbox in the M5 not only helps the driver to squeeze the most out of the engine’s prodigious performance but also offers a host of safety features. In critical situations, when shifting down on a slippery road for example, the gearbox opens the clutch in a split second in order to prevent the car from suddenly swerving out of control as a result of excessive drag torque at the driven wheels.

A further practical SMG feature is the so-called climbing assistant, which has up to now been featured exclusively in the M3 and allows for hill starts with virtually no roll-back. This effect is achieved by brake system intervention and can be taken advantage of in the sequential as well as the automated mode, irrespective of the direction of travel. The function is activated by applying the foot brake. As soon as the driver releases the brake pedal, the M5 is able to set off without rolling back in an uncontrolled manner.

The intelligent transmission on steep gradients.

The so-called hill detection adjusts the shift points on gradients and descents. This prevents gear hunting when driving uphill. When going downhill, the hill detection holds the lower gears for longer in order to make effective use of the engine’s braking power. In addition, with the gearbox in D mode, gear selection is adjusted to the steepness of the gradient.
These functions are only possible because the SMG control unit and the engine management system in the M5 closely communicate with each other via a particularly powerful CAN data bus, which connects the MS S65 engine management system with the SMG control unit, which is linked up to
twelve redundant SMG sensors. In this way, the SMG control unit receives from the MS S65 the relevant data on the accelerator position, wheel and engine speeds, temperatures, steering angle and key memory. Moreover,
the SMG and DSC directly communicate with one another.

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