The new E 55 AMG represents the latest chapter in the illustrious history of supercharged Mercedes-Benz cars. An era that began in the late 1920s with the legendary supercharged Mercedes-Benz S to SSKL models enjoys its most exalted moment yet in the shape of the new sports Saloon.
With the latest E 55 AMG, Mercedes-AMG has created a worthy successor to the popular outgoing model, of which some 12,000 units rolled off the production line between 1997 and 2001. This makes the outgoing E 55 AMG the most successful AMG model in the company’s 35-year history. The might of the AMG supercharged V8 engine with 5.5-l displacement, the Formula 1-style steering-wheelmounted gearshift buttons, the AIRMATIC DC air suspension tuned to AMG specifications and a full complement of equipment - including AMG 18-inch twin-spoke wheels, AMG bodystyling and nappa/nubuk leather upholstery - together enable the new E 55 AMG to present an unrivalled package and take a leading position ahead of the other standard sports saloons in its segment.
The high-performance 5.5-litre powerpack from the SL 55 AMG develops 350 kW/476 hp at 6100 rpm and maximum torque of 700 Nm in the new E 55 AMG. These imposing figures are rooted in the majestic torque of the supercharged eight-cylinder engine. The AMG engine delivers 560 Newtonmetres of torque to the crankshaft as low down as 1500 revs per minute, and this grows to 650 Nm only 500 rpm later. The peak torque of 700 Nm is available anywhere between 2650 and 4500 rpm. The supercharged V8 thus develops 34 percent more power and 32 percent more torque than the outgoing model with its naturally aspirated eight-cylinder engine.
This withering power leaves its rivals trailing in its wake, whilst also propelling the four-door Saloon to some extraordinary performance figures. 4.7 seconds is all it takes for the Mercedes-Benz E 55 AMG to reach the 100 km/h mark, whilst 200 km/h is clocked up in just 16.1 seconds - on the way to a top speed of 250 km/h (electronically limited). NEDC combined fuel consumption stands at 12.9 litres per 100 kilometres.
One of the technical highlights of this highly sophisticated supercharged AMG engine is the mechanical charger positioned between the cylinder banks, which exerts a maximum 0.9 bar pressure on the 5.5-l eight-cylinder engine. Inside the compact supercharger, two Teflon-coated aluminium shafts rotate at a maximum of 23,000 revs per minute, pushing 1850 kilograms of air per hour into the eight combustion chambers.
The scroll compressor is not permanently running and is only activated at a certain engine speed and load condition. The engine electronics send the command to an electro-magnetic coupling, which immediately switches on the compressor by means of a separate poly-V-belt. The system has two advantages: on the one hand, it means that the compressor can be activated in a split-second and the driver’s acceleration command implemented directly and without delay, and on the other, the engine consumes less fuel in part-throttle operation when the compressor is not in use.
Integrated into the compact charger module is the engine-mounted intercooler, which works according to the extremely effective principle of an air/water heat exchanger. The air compacted by the compressor is channelled along to a water source, which flows in a separate circuit from the engine coolant. In this way, the air can be cooled before it enters the eight combustion chambers - the supercharged eight-cylinder powerpack makes maximum power and torque available at all times, regardless of the air temperature outside. The low-temperature circuit is integrated into the cooling module along with the engine radiator and the air conditioning condenser, whilst the large air inlet in the AMG front apron ensures optimum air flow through the vehicle.
The power of the engine radiator’s 850-watt intake suction fan has been boosted to take into account the increased cooling requirement of the AMG supercharged V8 engine. The engine’s oil cooling is also more efficient. In the E 55 AMG’s right-hand wheel arch is a separate oil cooler, which is supplied with cooling fresh air by the front apron, whilst a fan is also activated if necessary.
The wealth of experience built up by Mercedes-AMG engineers in motorsport and the construction and development of high-performance engines came in useful with the supercharged V8 engine which powers the E 55 AMG.
The following components had to be newly constructed:
- the crankcase has been reinforced with special stiffening ribs and side bolts
- the crankshaft is precision balanced. Modified bearings and a more resistant material have been used to take into account the high torque of the super-charged engine. The stroke has been extended from 84 to 92 millimetres
- the pistons are made of a special, extremely temperature and pressure resis-tant material and enjoy the benefit of oil injection cooling
- the connecting rods are forged and their bearings made of extremely durable materials
- the oil supply, with sump, catch tray and more efficient pump, was subjected to thorough modifications
- the cylinder heads, of which the inlet and outlet ducts have been optimised to take into account the increased air mass flow
- the camshafts have extended valve opening times, which improves the fuel supply to the combustion chambers
- the valve train has a twin spring assembly, which allows the rated engine speed to be increased from 5600 to 6100 rpm
- the engine electronics take on additional tasks in the AMG engine, such as the logic-controlled activation of the compressor