The new V8 Power Unit for the BMW M3.
More in Every Respect:
Its name alone spells out the epitome of ultimate driving pleasure:
This applies not only – but particularly – to the power unit: After 15
The benchmark the new power unit was required to exceed could hardly have been greater: BMW’s 3.2-litre straight-six has gained fame and admiration the world over, receiving a long list of awards and prizes. Acknowledged several times as the “Engine of the Year” and developing a supreme 252 kW/343 hp in its last version, this power unit made the BMW M3 not only the ultimate performer in the segment of high-performance sports cars, but also a genuine best seller.
The fact still remains, however, that everything has its time. And now
The specifications of this new high-performance power unit alone clearly confirm the enormous progress this engine has to offer. Engine displacement is 3,999 cc, maximum output is 309 kW/420 hp. Peak torque of 400 Newton-metres or 295 lb-ft is just as impressive as the top engine speed of 8,300 rpm. So clearly, the new BMW M3 is striking out for the top right from the start through its thrilling performance.
Ideal dimensions for performance at its best.
Displacing 500 cc per cylinder, the new V8 power unit meets the ideal concept of the most demanding engine designers right from the start through its engine dimensions alone. And the other design criteria – all the way from the engine’s dimensions and filling capacities through the number of components to the weight of the engine – likewise represent the very best achievable today.
Over and above these qualities, the new eight-cylinder offers all the
In terms of specific output, the new V8 significantly exceeds the
The M high-speed engine concept allows optimum transmission and final
drive ratios further enhancing the impressive thrust and power of the
engine. Indeed, BMW M’s engineers have found a new dimension in
The second factor crucial to thrust and performance on the road, engine torque, amounts to a mighty 400 Newton-metres or 295 lb-ft at 3, 900 rpm on the new V8 power unit. And about 85 per cent of the engine’s maximum torque is available throughout the enormous engine speed range of 6,500 rpm, with 340 Newton-metres or 251 lb-ft available from just 2,000 rpm.
High engine speed, low weight.
Mass (which, ultimately, means weight) is bad for acceleration – it
makes any physical body seeking to accelerate slower and more sluggish.
Precisely this is why BMW’s new V8, weighing a mere 202 kg or 445 lb, is
a genuine lightweight, saving some 15 kg or 33 lb versus the
six-cylinder power unit in the previous model. In other words, the new
engine easily sets off the
Even so, the limits to physics inevitably approach step-by-step with
increasing engine power: At 8,300 rpm, each of the eight pistons is
moving at a speed
Engine block straight from BMW’s Formula 1 foundry.
The engine block of the new eight-cylinder comes straight from BMW’s
light-alloy foundry in Landshut near Munich, where BMW also builds the
engine blocks for the Company’s Formula 1 racing cars. The cylinder
High engine speeds, compression forces and temperatures cause extreme
loads acting on the crankcase. Hence, the crankcase is compact in its
Double-VANOS with low-pressure operation.
With its extremely short control times, variable double-VANOS camshaft management perfects the cylinder charge cycle, reducing charge losses and improving engine output torque and response, as well as fuel economy and emission management.
Developed especially for the new eight-cylinder, the M double-VANOS now featured on the new engine requires no more than normal engine oil pressure in order to operate at maximum speed. As a function of load and engine speed, this sophisticated unit consistently sets the optimum valve angle synchronised to the ignition timing and injection volume.
Consistent and reliable oil supply even under extremely dynamic driving conditions.
Two volume-flow controlled pendulum slide cell pumps supply the eight-cylinder efficiently with lubricant, consistently delivering exactly the right amount for the engine. Wet sump lubrication optimised for engine dynamics, in turn, ensures appropriate lubrication also in extreme braking manoeuvres.
The entire system features two oil sumps – a small one in front of the
Eight individual throttle butterflies with electronic control.
Individual throttle butterflies for
each cylinder, a technology commonly used in motorsport, are the ideal
solution to give the engine an immediate, direct response at all times.
The new power unit in the BMW M3 therefore comes with eight individual
throttle butterflies, four on each row of cylinders operated by separate
actuators. This high-tech throttle butterfly management is
Flow-optimised air intake.
To ensure an immediate response and
superior dynamics of the engine
Innovative exhaust system.
Through its design and configuration, the exhaust system for the new V8 power unit optimises the cylinder charge cycle, ensuring an optimum surge of power and torque at all times. And again, this component has been designed and built from the start for consistent lightweight qualities.
The exhaust manifolds are made in an internal high-pressure remoulding
process, the desired contours of the stainless-steel pipes being shaped
Exhaust emissions are cleaned by no less than four catalysts and the engine naturally complies both with the European EU4 standard and the US LEV 2 requirements.
Even better performance than before: the engine control unit.
The engine control unit featured on the V8 has also been upgraded to an
as the respective position of the eight individual throttle butterflies.
Yet a further function of the engine control unit is to perform a wide range of on-board diagnostic functions with various diagnostic routines for servicing at the workshop as well as other functions and the efficient management of peripheral units and systems.
An outstanding highlight in engine management: ion flow technology.
A particular highlight in engine management is ion flow technology
detecting any knocking in the engine as well as the risk of misfiring or
miscombustion. Contrary to conventional processes and technologies, this
The spark plug therefore serves as an actuator for the ignition and as a
sensor observing the combustion process, distinguishing in this way
Greater efficiency and dynamics provided by Brake Energy Regeneration.
To further enhance the efficiency of the new V8 power unit, Brake Energy
Regeneration ensures intelligent engine current management concentrating
the generation of electric power for the on-board network on the overrun
phases and the application of the brakes. This serves to charge the
car’s battery without tapping on engine power and, accordingly on the
energy contained in the fuel burnt. As long as the engine is running
Apart from particularly efficient generation of electric current, this
in Every Respect:
An exceptional power unit for an exceptional sports car: The V8 power
unit featured in the new BMW M3 raises the driving pleasure offered by
V8 power units have always been acknowledged as fascinating machines
making the heart of the genuine aficionado skip a beat – particularly if
A similar thrill is provided in Formula 1, the highest and most challenging level of motorsport, where once again the eight-cylinder sets the standard and marks the latest development in technology. And the similarities between the BMW Sauber F1 Team’s power unit, on the one hand, and the power unit featured in the new BMW M3, on the other, are unmistakable.
To round off this perfect combination, the BMW M3 teaming up with the
The engine’s specifications alone clearly prove the enormous progress
achieved in changing over from the straight-six power unit which has
dominated the scene for more than 15 years to the new eight-cylinder:
So 20 years after the first BMW M3 established the then brand-new segment of high-performance sports cars, the fourth generation paves the way into an unprecedented dimension of driving pleasure.
After 15 years: goodbye to the six-cylinder, hello to the V8.
Following the rule that “there is always room for improvement”, even the
engine of the “Car of the Century”, as the French motor magazine “Auto
Plus” euphorically lauded the second-generation BMW M3 15 years ago,
So in introducing the fourth generation of the BMW M3, BMW M is also making a change within the engine compartment, opening up the door to the brand-new V8.
Maximum output of 309 kW/420 hp also sets
an appropriate distance to the top engine in the “regular” BMW 3 Series,
the 3.0-litre straight-six with
The ideal formula for the engine designer: 8 x 500 = 4,000.
Eight cylinders, four litres capacity. Specifications of this kind alone
make the dream of the engine designer come true on the new power unit.
High-speed engine concept entering a new dimension.
The designers and engineers responsible for the new power unit have
nevertheless remained faithful to the high-speed engine concept so
typical of BMW M. Indeed, they have even raised this concept to an
unprecedented level, the new V8 reaching maximum engine speed of 8,300
rpm, a figure so far seen only in motorsport engines and a handful of
exotic, hand-built cars.
The high-speed engine concept is however a traditional forte of BMW M
GmbH’s high-performance natural aspiration engines, generating enormous
power and performance from high engine speeds. This avoids the
Through the high-speed engine concept, the engine development
specialists at BMW M GmbH thus ensure that the spontaneity of the
engine, its instan-taneous response to the driver’s wishes, reflects the
great demands made of an M Car and its overall concept. And so, in its
Taking Formula 1 as a role model and paving the way through
A further significant point is that the eight-cylinder boasts all the features and qualities so typical of BMW M, such as double-VANOS, individual throttle butterflies, and high performance engine electronics. At the same time the number of cylinders, the high-speed engine concept and the low weight clearly indicate that the engineers responsible for the new eight-cylinder have been inspired by another eight-cylinder – the unique engine featured in the BMW Sauber F1, the engine currently raced by the Team in the highest realms of motorsport. And indeed, the two power units share a number of features not only in their basic technological principles, but also in their production methods and materials clearly borne out by the transfer of technology from motorsport to series production.
One difference, however, will always remain: The BMW M3 is required to
offer outstanding performance not only on racing weekends and therefore
features a high-performance power unit fully suited for everyday use and
Twenty per cent more power – a new dimension in driving dynamics.
A new BMW M3 must offer one feature in particular: even more power.
In its specific output, the eight-cylinder easily exceeds the benchmark of 100 hp per litre acknowledged as the standard for a particularly sporting and dynamic power unit. But even so, power is not everything. Instead, the dy-namic experience offered by a car is borne out in particular by its acceleration and performance in gear at all speeds resulting also from the weight of the vehicle and the sheer thrust and muscle of the engine.
The engine is an important factor in determining the weight of a car,
By comparison, the 294 kW/400 hp V8 in the predecessor to the current
BMW M5 weighed 240 kg or 529 lb. So despite the extra power, the new
engine is more than 15 per cent lighter. Indeed, it is approximately 15
High-speed engine concept for superior power and torque in practice.
The second factor crucial to driving dynamics, the power and thrust
actually conveyed to and by the drive wheels, results from engine
torque and the overall transmission ratio. At 400
Newton-metres or 295 lb-ft at 3,900 rpm, maximum torque of the new
eight-cylinder is approximately 10 cent higher than the peak torque of
the former straight-six, and the engine develops an equally superior 340
Newton-metres or 251 lb-ft at just 2,000 rpm.
This is clearly reflected by the performance characteristics of the new
Last but certainly not least – and indeed quite crucial in terms of
overall qualities – the high-speed
engine concept with its M-specific features allows use of the optimum
transmission and final drive ratios and thus guarantees
The effect provided in this way is borne out by a clear example:
Whenever a cyclist shifts down on an uphill gradient, he has to turn the
pedals faster, but in return he can ride up virtually any hill. Should
he, on the other hand, remain
High speed, low weight.
The fact remains that more power alone – that is higher torque – is not
The other side of the coin is that the M high-speed engine concept is
extremely demanding in technological terms: While the former
straight-six was still limited electronically to maximum engine speed of
8,000 rpm, the
Given this kind of power and such unique technology, the engine of the
new BMW M3 shifts the limits of technology in series engine production
Targets in the design and construction process: compact, stiff, light.
In developing BMW’s new eight-cylinder power unit, the engineers and
other specialists sought to reduce all moving masses to an absolute
The decision to choose a 90° angle was taken on account of the efficient
compensation of mass forces provided by this geometry, serving to
minimise vibrations and maximise motoring comfort. By and large,
Engine block from BMW’s Formula 1 foundry.
The engine block featured on the new BMW M3 comes from BMW’s light-alloy
foundry in Landshut near Munich, which also builds the engine block for
BMW’s Formula 1 racing cars. The cylinder crankcase is made at the
foundry in a low-pressure die-casting process from an over-eutectic
aluminium-silicon alloy, with at least 17 per cent silicon. The cylinder
liners, in turn, are formed
Since high engine speeds, high compression forces and high temperatures
exert extreme loads on the crankcase, the crankcase is very compact in
its design and dimensions and built as a very stiff bedplate structure,
a concept which has already proven its qualities in motorsport. Made of
die-cast aluminium, the bedplate features grey-cast-iron inlays ensuring
very precise support of the crankshaft. In particular, this structure
keeps main bearing
With the distance between cylinders measuring only 98 millimetres or
3.86´´, the crankshaft made of forged,
high-strength steel is relatively short, making it very stiff in terms
of flexural and torsional strength and reducing the weight
Lightweight construction specifically on all moving masses.
The weight-optimised box-type pistons are cast out of a high
temperature-proof aluminium alloy and coated with iron. This reduces
their weight to
The pistons are cooled by oil spray jets connected to the main oil pipe.
Measuring 140.7 millimetres or 5.54´´
in length, the cracked trapezoidal connecting rods are made of a
high-strength steel-magnesium alloy.
The single-piece aluminium cylinder
heads feature four valves per cylinder in characteristic BMW style. The
valves weighing 42 grams each are activated
The engine always keeps a cool – cylinder – head.
Compared with conventional systems, the cross-flow cooling concept
Double-VANOS – but with low instead of high pressure.
Focusing on the engine concept, the engineers at BMW M sought from the
start to increase engine output through an optimum charge cycle at high
engine speeds. Quite simply, this is because reduced charged cycle
losses offer not only more power, but also an improved torque curve and
optimum engine response as well as a further reduction of fuel
consumption and lower emissions. And precisely these are the benefits
offered by variable
With its extremely short adjustment times, double-VANOS now also perfects the cylinder charge cycle in the eight-cylinder power unit of the new BMW M3. Under low loads and at low engine speeds, for example, double-VANOS ensures a higher valve overlap and, as a result, better internal recirculation of exhaust gasses. This, in turn, reduces charge cycle losses and helps to minimise fuel consumption.
The level of power delivered by the engine depends on the position of
The advantage is that the low-pressure M double-VANOS developed for the
eight-cylinder is able, unlike the high-pressure VANOS featured on the
Reliable oil supply even under extremely dynamic conditions.
The high standard of driving dynamics offered by the BMW M3 obviously
calls for a sophisticated supply of oil to and within the engine.
The eight-cylinder is reliably supplied with lubricant in all driving situations by two volume flow-controlled pendulum shift cell pumps consistently providing exactly the right amount of oil required by the engine. This is ensured by a change in eccentricity (off-centre arrangement) of the inner rotor in the pump versus the pump housing as a function of oil pressure in the main oil duct.
In consideration of the physical forces and loads encountered in an
extremely dynamic driving situation, it is conceivable that when the
driver applies the brakes particularly hard, for example, the supply of
oil to the oil sump serving as an interim storage reservoir would not be
sufficient, particularly as the
The new eight-cylinder power unit from BMW M also comes with electronic
oil level control determining the level of oil by means of a sensor
fitted in the oil sump. The data thus measured is transmitted by a
serial databus to the engine management evaluating this data by means of
various algorithms. The value thus obtained, corrected by the car’s
lateral and longitudinal acceleration,
Eight individual throttle butterflies with electronic management.
In motorsport this is standard technology, in “regular” cars it is quite
The power unit of the BMW M3 so closely related to motorsport comes
As a result, it takes the throttle butterflies only 120 milliseconds to
reach their maximum opening point – about as long as a routined driver
needs to press down the gas pedal. The result, first, is a sensitive and
smooth response of
Flow-optimised air intake.
To give the engine an instantaneous, immediate response, the air volume
on the intake side of the throttle butterfly must be reduced to an
From front to rear, the entire flow of intake air in the new
eight-cylinder power unit does not require the usual hot-film air mass
flow meter with its obligatory sensors. Instead of determining engine
load by means of such elaborate sensors, therefore, which would also
create disadvantages in air guidance due to the geometry of the
components involved, the V8 power unit of the new BMW M3 uses the engine
control unit to perform this function. To do this,
The length and diameter of the eight intake funnels also helps to ensure
an optimum charge effect in the oscillating tube. Like the single-piece,
extra-large air collector, the funnels are made of a light composite
material with a
Innovative exhaust system.
Though its design and configuration, the exhaust system also serves to
optimise the cylinder charge cycle. To give the eight-cylinder power
The development engineers have likewise given their full attention to
High-thrust innovation for ultra-thin pipes.
BMW M GmbH’s particular innovative strength in engine construction is
also borne out by the production methods used. Indeed, one example dates
back all the way to 1992, when BMW M GmbH became the first company to
Inner high-pressure moulding serves to shape the seamless
stainless-steel exhaust pipes from inside under a pressure of up to 800
bar. The result is pipes with extremely thin walls between 0.65 and 1.0
millimetres (0.0256 and 0.0394´´).
Clearly, this helps to optimise both the weight of the exhaust
At the same time this sophisticated technology allows moulding and
shaping processes previously not conceivable, as well as even better
Exceptionally clean and audibly dynamic.
Generally, only racing engines feature a fan-type exhaust manifold
leading out of the cylinders. But it almost goes without saying that the
new V8 also
The two catalytic converters – one in each exhaust pipe – are positioned close to the engine. These primary catalysts quickly reach their optimum operating temperature since the thin walls of the exhaust manifolds minimise any thermal inertia of the material while warming up, thus ensuring a very fast response after starting cold.
Two particular features of the catalytic converters are their low pressure loss and the high standard of mechanical strength.
Two additional tri-metal-coated catalytic converters then come further
down-stream, integrated in the underfloor of the car. Interacting with
Noise emissions are likewise exceptionally low. Apart from the two interim silencers, particularly the single-piece rear muffler in crosswise arrangement with its very large volume of 35 litres serves to reduce the noise level.
The new V8 power unit nevertheless boasts an exceptional sound and
Brake Energy Regeneration for greater efficiency and dynamic
Brake Energy Regeneration also serves on the new V8 power unit in
This highly efficient energy management related to actual driving
alternator when the engine is running under load: With the generation of
electric power being cut off when running under load, more drive power
With the number of charge cycles increasing as a result of such intelligent power generation, BMW combines this Brake Energy Regeneration tech-nology with modern AGM (absorbant glass mat) batteries able to withstand a much greater load than conventional lead acid batteries. In an AGM battery, the acid is held in micro-glass-fibre mats between the individual layers of lead, the battery thus remaining able to store energy over a long period even when charged and discharged regularly.
Even greater performance: the new engine management system.
The MSS60 engine management system is the central “brain” responsible
Benefiting from this highly sophisticated concept, MSS60 coordinates all
functions of the engine with the various other control units on the car.
Electronic throttle butterfly control measures loads and forces for
optimum management, measuring the driver’s commands by means of the
potentio-meter on the gas pedal and converting this signal into the
Engine management with a wide range of additional functions.
The MSS60 control unit is more than “just” a conventional engine
manage-ment system in the direct sense of the word. With its hardware,
Precisely this is why the driver of the new BMW M3 is also able, simply
As soon as the driver starts the engine, the control system automatically switches to the more comfortable of the two programs. The driver never-theless has the option to preconfigure and activate the change in programs in the MDrive control unit, which also offers another, extra-sporting and dynamic program.
Last but certainly not least, engine management also performs a wide
range of on-board diagnostic functions using various diagnostic routines
The highlight in engine management: ion flow technology.
One of the highlights of the engine control unit is ion flow technology
“Knocking” is undesired selfignition of fuel in the cylinder. Engines without knock control have a lower compression ratio and their ignition point comes later (retarded ignition), since the engine would suffer from going beyond the knock limit. However, this “safety margin” costs fuel, engine power, and torque.
By contrast, active knock control allows the engine to run with optimum
With conventional anti-knock control sensors measuring body sound are fitted outside on the cylinder. But the ability of such sensors to detect knocking in the combustion process decreases with increasing engine speed and a growing number of cylinders – and particularly such accuracy and reliability is essential on a fast-revving eight-cylinder in order to optimise combustion quality in the cylinders and, as a result, the service life of the battery and the exhaust emissions. Hence, ion flow technology measures the risk of knocking exactly directly where this phenomenon occurs – within the combustion chamber.
In this process the system uses a physical phenomenon resulting from the
high temperatures of up to 2,500 oC encountered in the
Measurement of ion flow thus provides information on the combustion
pro-cess directly where combustion takes place. The electronic “brain”
Using an innovative semi-conductor circuit to measure the control
voltage required and reinforcing/multiplying the incoming signals in a
Spark plugs taking on additional control functions.
This technology thus uses the spark plug in each cylinder to sense and,
Output and Torque Diagram.