by Adrian Dorofte and Adrian Andronic
e-mail: mercedesbenzblog@gmail.com

The new Mercedes-Benz E 63 AMG: Engine and power transmission

1. Engine: Top on power and efficiency

The AMG 5.5-litre V8 biturbo engine in the E 63 AMG delivers signature AMG high performance on all fronts. From top speed through torque generation, power delivery, engine sound and suitability for long trips to hallmark Mercedes reliability, the eight-cylinder engine with an output of up to 430 kW (585 hp) meets high expectations and leads the way in its segment. Today's challenges also include peak performance in terms of efficiency. The E 63 AMG continues to set new standards here – the AMG 5.5-litre V8 biturbo engine remains the most efficient series production V8 engine around. A look at the fuel consumption picture confirms its outstanding credentials: running on 9.8 litres per 100 kilometres in NEDC combined mode (E 63 AMG Saloon with rear-wheel drive), the E 63 AMG demonstrates in impressive fashion how fascinating dynamics and low fuel consumption can be combined to perfection.

As previously, the E 63 AMG is available in a choice of two power ratings: as the basic model with an output of 410 kW (557 hp) and 720 Newton metres of torque and as the S-Model rated at 430 kW (585 hp) and generating up to 800 Newton metres of torque. This represents an increase of up to 24 kW (32 hp) and 20 Newton metres in comparison to the respective predecessor models. The technical basis for this uprating results from adaptation of the engine application, an increase in peak pressure and a rise in the charge pressure from 0.9 to 1.0 bar. The engine experts at AMG have achieved compliance with the requirements of the particularly stringent EU6 emissions standard, which will not become mandatory until 2015, by optimising the injection timing with the aid of multiple fuel injection and by modifying the European on-board diagnostics.

From power delivery to engine sound, the AMG 5.5-litre V8 biturbo engine (internal designation M 157) makes every mile a sheer delight. The E 63 AMG picks up speed with effortless poise. A key factor here is the unique torque curve of the supercharged eight-cylinder engine from the AMG hand-finishing section in Affalterbach: 720 Newton metres of torque are available in the broad rev range from 1750 to 5250 rpm, the E 63 AMG S even disposing of as much as 800 Newton metres between 1750 and 5000 rpm. This results in vast pulling power in every speed range.


Overview of key data for the models available on the German market:

The technical highlights of the AMG eight-cylinder engine include:

- Direct petrol injection
- Biturbocharging
- All-aluminium crankcase
- Four-valve technology with camshaft adjustment
- Air-water charge air cooling
- Generator management
- ECO start/stop function

Two exhaust gas turbochargers located next to the cylinder banks supply the eight cylinders with fresh air. At their maximum speed of 185,000 rpm under full load, the two turbochargers force 1750 kg of air per hour into the combustion chambers. Thanks to their special, compact design – the turbine housings are welded to the exhaust manifold – there are significant space advantages, and the catalytic converters also heat up more rapidly.

The AMG V8 dispenses with the customary blow-off valve. This has enabled an extremely compact design for the compressor housing. To ensure agile responsiveness with no time lag, all the air ducts in the intake tract are as short as possible. The AMG experts have enabled the wastegate valve, which reduces the pressure in the exhaust system during negative load changes, to be vacuum-controlled via an electropneumatic converter. This allows dethrottling under partial loads, which in turn lowers the fuel consumption.

As was already the case in the AMG 6.0-litre V12 biturbo engine, the eight-cylinder direct-injection unit uses particularly efficient air/water intercooling. The low-temperature cooler with its water circulation is space-savingly accommodated within the V of the cylinder banks. It effectively cools down the intake air compressed by the turbochargers before it enters the combustion chambers, and maintains a constantly lower intake temperature under full load. The large radiator at the car's front end ensures defined cooling of the water circulating in the low-temperature circuit. Extremely short charge-air ducting makes for optimum responsiveness. The stainless-steel pressure pipes for the fresh and charge air are produced by the hydroforming process, have a wall thickness of only 0.8 millimetres and are designed for very low pressure loss.

All-aluminium crankcase with Silitec cylinder liners

The crankcase for the AMG 5.5-litre V8 biturbo engine is made of diecast aluminium. The low (dry) engine weight of 204 kilograms is the result of uncompromising lightweight construction methods and gives the vehicle balanced weight distribution. The bearing cover for the main crankshaft bearings, made of grey cast iron, is bolted to the crankcase for high rigidity. Cast-in Silitec cylinder liners ensure that the eight pistons operate with low friction.

Drilled ventilation holes in the crankcase lead to a higher output and fuel savings under partial load: above the bearing blocks there are longitudinally drilled holes which connect the adjacent crankcase cavities. Normally the upward and downward movement of the pistons causes air to be forced into and extracted from the sump, which leads to increased resistance and therefore a reduction in output. The ventilation holes prevent this by ensuring effective pressure compensation between the cavities.

The forged crankshaft made of high-grade 38MnS6BY steel alloy (a combination of the chemical elements manganese, sulphur, boron and yttrium) rotates in five main bearings, has eight counterweights and has been optimised with respect to torsional rigidity, inertia, low rotating masses and a long operating life. A two-mass viscous damper mounted at the front reliably eliminates vibrations. Each connecting rod journal on the crankshaft carries two forged, cracked connecting rods. In the interests of low mechanical friction and high wear resistance, the lightweight pistons have a metallic contact surface. Pressure-controlled oil-spray nozzles in the crankcase ensure that the highly stressed piston crowns are efficiently cooled.

Four-valve technology with variable camshaft adjustment

Perfect charging of the combustion chambers is ensured by large intake and exhaust valves, of which there are two per cylinder. The exhaust valves, which are subject to high thermal loads, are sodium-cooled and hollow in order to reduce weight. Four overhead camshafts operate the 32 valves via low-maintenance, low-friction cam followers. The infinitely variable camshaft adjustment within a range of 40 degrees on the intake and exhaust sides depends on the engine load and engine speed, leading to outstanding output and torque values. This also results in consistent idling at a low speed.

Depending on the engine speed, valve overlap can be varied for the best possible fuel/air supply to the combustion chambers and efficient removal of the exhaust gases. The variable camshaft adjustment is carried out electromagnetically via four pivoting actuators, and is controlled by the engine control unit. The camshafts are driven by three high-performance silent chains, which have considerable advantages with regard to noise comfort compared to cylinder roller chains.

Innovative oil supply and water cooling

Efficient oil delivery under all load and operating conditions is ensured by an oil pump with an electrically controlled compression stage. The oil pressure can be varied between 2 and 4 bar, which has advantages in terms of friction and fuel consumption. An extraction stage integrated into the oil pump for the two turbochargers prevents oil from being entrained into the charge air and exhaust gases, thereby helping to reduce emissions even further. Both the sump and the extraction point have been optimised for maximum lateral acceleration and efficient lubrication. The oil capacity is 10.5 litres.

The combined water/oil cooling system represents an intelligent solution: after a cold start, initially the engine oil is only cooled via the oil/water heat exchanger. If the cooling performance of the very compact cooler is insufficient, the flow is additionally directed through the external engine oil/air cooler by an oil thermostat. The advantage of this system is that the engine oil heats up more rapidly, as the engine coolant warms up more quickly and the oil is later cooled by the coolant. A selectable water thermostat ensures rapid warming of the coolant when starting the engine and driving off. Large intakes in the new front apron of the E 63 AMG ensure an effective flow of air to the water, engine oil, charge-air and transmission oil coolers.

The engine coolant is cooled using the particularly efficient crossflow principle. There is a transverse flow of coolant through both the crankcase and the cylinder heads. Additional cooling slots in the cylinder head allow more efficient cooling of the combustion chambers, which entails advantages during combustion, enabling earlier ignition timings to be chosen without incurring the risk of knocking.

Generator management and optimised belt drive

The ECO start/stop function, which in "Controlled Efficiency" mode shuts down the eight-cylinder engine every time the vehicle is stationary, is not the only feature contributing to low fuel consumption. Generator management also helps to enhance efficiency: whenever the engine is on the overrun or when braking, kinetic energy is used to charge the battery rather than being wasted as heat in the usual way. In all other operating modes a combination of onboard network and generator management enables the generator to be kept at a low voltage. This reduces the load on the engine and makes for fuel savings of around 0.15 litres per 100 kilometres according to the NEDC standard, and up to 0.2 litres per 100 km in city driving with its frequent overrun and braking phases.

Highly efficient engine electronics for every function

All the engine functions are executed and controlled by a particularly efficient control unit. This state-of-the-art engine computer not only controls direct petrol injection, charge pressure, camshaft adjustment and variable oil supply but also communicates with all the other onboard control units, such as those of the AMG SPEEDSHIFT MCT 7-speed sports transmission. The microprocessor has more than 30,000 different parameters and functions stored in its memory, and is able to perform up to 260 million individual operations per second. To reduce the load on the engine control unit, the eight individual ignition coils have an integral electronic module on each cylinder. This ensures a strong ignition spark at all engine speeds and under all load conditions. The highly precise fuel distribution of the piezo-electric injectors is handled by eight high-voltage output stages.

Lightweight AMG sports exhaust system for a characteristic sound signature

The twin-pipe AMG sports exhaust system has a pipe cross-section of 70 millimetres from the manifolds to the rear silencers. The sound design is characterised by a perfect synthesis of tangible dynamism and hallmark Mercedes comfort on long journeys. Emotional appeal during acceleration and double-declutching combines with the appropriate restraint at steady speeds. A distinctive, signature AMG eight-cylinder sound emanates from the striking chrome twin tailpipes of the sports exhaust system.

Engine production – a tradition of hand-built excellence

Like all AMG high-performance engines, the biturbo eight-cylinder engine is assembled by hand in the hand-finishing section at AMG, observing the most stringent quality standards. Highly qualified engine fitters assemble the M 157 according to the philosophy "one man, one engine". The signature on the characteristic AMG engine plate attests to the painstaking care exercised by the fitter.


2. Power transmission: All-wheel drive for perfect dynamics

The AMG SPEEDSHIFT 7-speed sports transmission and the new, performance-oriented AMG 4MATIC all-wheel drive complement the AMG 5.5-litre V8 biturbo engine to perfection. These two high-tech systems raise the driving dynamics of the E 63 AMG to a new, unprecedented level.

The performance-oriented AMG 4MATIC all-wheel drive is optionally available for the E 63 AMG rated at 410 kW (557 hp). The E 63 AMG S with 430 kW (585 hp) engine comes with all-wheel drive as standard. The technical basis is provided by a transfer case for the additional power take-off to the driven rear axle. This transfer case is integrated compactly into the AMG SPEEDSHIFT MCT 7-speed sports transmission and requires virtually no additional installation space. The torque is transmitted from the power take-off via a propeller shaft to the front axle. Power transmission from the front-axle differential to the front-left drive shaft is effected via an intermediate shaft which passes through an encapsulated shaft duct in the engine oil pan. The compact design results in additional weight of only around 70 kilograms.

In contrast to the series production vehicles, on the E-Class all-wheel drive models the engine torque is distributed to the front and rear axles at a ratio of 33 to 67 percent. This clearly rear-biased power distribution provides for signature AMG high driving dynamics and superlative driving enjoyment. The 3-stage ESP® has been tailored specifically to the permanent all-wheel drive system. In "SPORT Handling" mode, ESP® Curve Dynamic Assist performs selective braking intervention on individual wheels in the interests of high agility, thereby avoiding understeering when turning and cornering. In bends, specific brief braking of the inner rear wheel results in defined cornering of the vehicle.

The 3-stage ESP® system offers three individual control strategies at the push of a button: the ESP® button on the AMG DRIVE UNIT enables the driver to choose between the stages "ON", "SPORT Handling" mode and "OFF" – the display in the AMG instrument cluster indicates the currently active state. In "ESP ON" mode, the system initiates braking intervention on one or more wheels and reduces the engine torque on detecting that the operating conditions are becoming unstable. In "SPORT Handling" mode, the intervention thresholds in response to over- or understeering and the accompanying engine torque intervention allow higher levels of driving dynamics and corresponding drift angles. This provides for considerably enhanced driving enjoyment. Pressing the ESP® button longer activates "ESP OFF". This mode avoids reducing the engine torque in the interests of greater driving dynamics and even more fun at the wheel. "ESP OFF" should only be used by experienced drivers on cordoned-off race tracks. In both "SPORT Handling" mode and "ESP OFF", all the ESP® safety functions are available when braking.

Enhanced driving safety on wet or wintry road surfaces

The AMG 4MATIC all-wheel drive also enhances driving safety and grip on wet or wintry road surfaces. Optimum traction is guaranteed by a multi-disk clutch with a locking effect of 50 Newton metres which exploits the frictional connection potential of all four wheels to the full on snow and ice in particular. This set-up enables high levels of traction by harnessing the dynamic shift in axle load toward the rear that occurs during acceleration to deliver more drive torque to the rear wheels.

However, the multi-disc differential lock is also able to shift the drive torque between the front and rear axles, varying the split between 30:70 and 70:30 as the road conditions dictate. Consequently, intervention by the 3-stage ESP®, 4ETS or ASR electronic control systems can be delayed for as long as possible and the bulk of the drive torque converted into tractive power, even on slippery roads. All control system interventions go virtually unnoticed, yet drivers still know straight away if they are driving near the limit, as a yellow warning symbol will flash in the AMG instrument cluster. This serves as a clear prompt to adapt the driving style to the road conditions.

E 63 AMG S-Model with differential lock on the rear axle

The E 63 AMG S sees Mercedes-AMG going one step further. True to AMG's "Driving Performance" brand claim, a mechanical differential lock is fitted on the rear axle of the most powerful E-Class model. This high-tech package results in a further increase in traction, ultimately leading to even greater driving dynamics and enhanced driving enjoyment, especially on the race track.

Exclusive AMG SPEEDSHIFT MCT 7-speed sports transmission

RACESTART, double-declutching function, seven gears, four transmission modes and stop/start function: the AMG SPEEDSHIFT MCT 7-speed sports transmission in the E 63 AMG combines extreme emotional appeal, maximum driving pleasure and optimum economy. The transmission boasts a thrilling combination of unique options which no other automotive manufacturer is able to offer in this format.

The sports transmission is exclusive to Mercedes-AMG and combines the sporty, direct and agile responsiveness of a manual transmission with the maximum comfort of an automatic transmission. MCT stands for Multi-Clutch Technology and indicates that only clutch elements are employed to perform gearshifts. A compact wet start-up clutch, which runs in an oil bath, replaces the conventional torque converter. Thanks to its low rotational inertia, the transmission responds instantaneously and dynamically without the losses typical of a torque converter transmission – thereby helping to save fuel. The AMG sports transmission also impresses with its low weight of just 80 kilograms, which has been made possible through the use of lightweight magnesium for the transmission housing. Vibrations are effectively eliminated by a new, two-stage torsion damper, with resulting benefits in perceived passenger comfort.

ECO start/stop function fitted as standard

The ECO start/stop function fitted as standard is permanently active in fuel-efficient "Controlled Efficiency" ("C") driving mode. Once the driver comes to a halt, e.g. at a red traffic light or in a traffic jam, the engine is automatically switched off. When the brake pedal is released or the accelerator is depressed, the engine is immediately restarted and the car is able to move off quickly. Intelligent technology guarantees a comfortable and immediate starting procedure: a crankshaft sensor which recognises the direction of rotation registers the rest position of all eight pistons. For an automatic engine start, the cylinder with the most favourable piston position receives an injection of fuel into its combustion chamber. The precise piezo-electric injectors greatly assist this process, as they make particularly fast starts possible.

The engine management system ensures that the engine is only switched off if certain preconditions are met. The starter battery must have sufficient charge, for example, and the engine must be at the necessary operating temperature for efficient emissions control. The same applies to the interior temperature selected by the driver: if this has not yet been reached, the engine is not switched off when the car comes to a stop. The onboard network management system ensures that active audio, telephone or video functions are not interrupted by the start/stop function.

A green "ECO" symbol shows the driver when the start/stop function is active. Should one of the above criteria be preventing activation of the system, this is shown in the central display by the message "Start/stop inactive" and a yellow "ECO" symbol. In the more performance-oriented driving modes "S" (Sport), "S+" (Sport plus) and "M" (Manual), the start/stop function is always deactivated.

Fuel-efficient Controlled Efficiency ("C") drive mode

In adapting the MCT sports transmission to the AMG 5.5-litre V8 biturbo engine, the AMG engineers paid special attention to the new driving mode Controlled Efficiency ("C"). The emphasis was on attaining minimum engine speeds in the highest possible gears for all driving situations. When moving off in "C", the transmission always selects second gear and shifts markedly early to the next-highest gears if the driving style permits. At 60 km/h for instance, sixth gear will already be engaged – improving not only fuel consumption but also noise levels. Thanks to its powerful, readily available torque even at low engine speeds, the AMG V8 biturbo unit is absolutely ideal for this style of driving. Controlled Efficiency also means convenient gearshifts and a "soft" accelerator response set-up for outstandingly smooth power transfer.

Drive modes "S", "S+" and "M" for even greater driving pleasure and dynamism

In addition to Controlled Efficiency ("C"), three transmission modes are available to meet the demands of drivers looking for a more dynamic ride: in "S" (Sport) mode, the engine and transmission take on a much more agile character. Accelerator pedal movements trigger a more direct traction response, making the downshifts more spontaneous. The engine speed is allowed to reach a higher level in each gear, while the gearshifts in "S" are around 25 percent faster than in "C". Turning the rotary switch on the AMG DRIVE UNIT a notch further to the right activates "S+" mode. Sport plus shifts the gears another 25 percent faster than in "S". The same applies to the manual shift mode "M". In "S+" and "M" modes, gearshifts at full throttle take just 100 milliseconds.

The engine management system also partially suppresses cylinders in "S", "S+" and "M" modes: precisely interrupting ignition and injection under full load for brief periods leads to even faster gearshifts than before. An appealing side effect of this lightning-fast process is a highly emotional sound in response to every gearshift with wide open throttle.

Ultra-fast, spontaneous multiple downshifts are another forte of the AMG SPEEDSHIFT MCT 7-speed sports transmission. For instance, kickdown allows gearshifts straight from seventh down to fourth gear, or from fifth to second. In the "S", "S+" and "M" driving modes the automatic double-declutching function is active. Every manual or automatic downshift is accompanied by precisely metered double-declutching – with increasing intensity from "S" through "S+" to "M". And this not only adds to the driver's emotional experience: the load-free downshift minimises load-change reactions, which pays particular dividends when braking into bends – and also enhances safety in the wet
or on ice.

No automatic downshifts in manual "M" mode

In manual “M” mode the driver also benefits from the high torque of the V8 biturbo engine, as there is no automatic downshift under full load and kickdown; the transmission remains steadfastly in the selected gear. Moreover, the 7-speed sports transmission does not perform an automatic upshift in manual mode when the rev limit is reached. In “M” mode the AMG instrument cluster displays the current gear and provides the driver with a visual warning of the need for an upshift just before the needle reaches the red zone. This means that a particularly sporty driver can use the superior performance potential to its fullest extent. When approaching the lower rev limit, e.g. when braking the vehicle, there is an automatic downshift to the next lower gear.

The powerful electronic transmission control unit with integrated 200 MHz processor controls spontaneous downshifts – when the driver suddenly needs power for dynamic acceleration, for example.

AMG DRIVE UNIT with RACE START function

The AMG DRIVE UNIT is the central control unit for the AMG SPEEDSHIFT MCT 7-speed sports transmission and all driving dynamics functions. On the left next to the selector lever is the electronic rotary switch to select the four drive modes, including activation of the RACE START function. Underneath are three buttons for additional functions: the first controls the 3-stage ESP®, the second the AMG RIDE CONTROL sports suspension.

The third, bearing AMG lettering, is used to store the personal set-up for transmission programme, suspension mode and 3-stage ESP®. Briefly pressing the AMG button brings up the configuration options, whilst holding down the button allows you to programme the required set-up - this is confirmed by an audible signal. The current settings may be viewed in the AMG instrument cluster by pressing the AMG button at any time.

The Race Start function delivers maximum dynamism: while the vehicle is at a standstill, the driver is able to activate SPORT Handling mode and press the brake pedal with his left foot. Having preselected the Race Start program using the rotary switch, a confirmation message comes up on the AMG central display. The driver then simply needs to confirm the Race Start function by pulling the "Up" shift paddle once, fully depressing the accelerator and taking his foot off the brake. The optimum start-up engine speed is set fully automatically and the E 63 AMG accelerates away with flawless traction – all the way up to top speed, if so required. The driver does not need to shift gear manually; the AMG MCT transmission changes gear in lightning-fast shift times.


~ Official photos and details courtesy of Mercedes-AMG GmbH ~

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