Mercedes-Benz AMG power and efficiency

Top on power and efficiency

• AMG 5.5-litre V8 biturbo engine with up to 430 kW
• Highest power and torque in its segment
• Fascinating power delivery, tractive power and engine sound
• Compliance with EU6 emissions standard right from the
  market launch

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 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, 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  and 720 Nm of torque and as the S-Model rated at 430 kW and generating up to 800 Nm of torque. This represents an increase of up to 24 kW
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 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 Nm of torque are available in the broad rev range from 1750 to 5250 r/min, the E 63 AMG S even disposing of as much as 800 Nm between 1750 and 5000 r/min. This results in vast pulling power in every speed range

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

* electronically limited

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 cross-flow 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.