Mercedes-Benz AMG power and efficiency

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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

Mercedes-Benz

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

E 63 AMG

Sedan

E 63 AMG S

Sedan

Displacement 5461 cc 5461 cc
Output 410 kW at 5500 r/min 430 kW at 5500 r/min
Max. torque 720 Nm

at 1750-5250 rpm

800 Nm

at 1750-5000 r/min

Fuel consumption

NEDC combined

9.8 l/100 km 9.9 l/100 km
CO2 emissions 230 g/km 232 g/km
Acceleration

0-100 km/h

4.2 sec 4.1 sec
Top speed 250 km/h* 250 km/h*

* 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.

Mercedes-Benz AMG

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.