August 19^th, 2003

SLR McLaren has a revered heritage

BACK in the mid-1950s, three letters - SLR - acquired a hallowed status, as a Mercedes-Benz racing car of that name set new standards in the world of high-class Gran Turismo vehicles.

Visually breath-taking and, thanks to innovative technology, superior to its rivals in terms of performance and handling, it spawned a legend.

Mercedes-Benz and McLaren have successfully imbued the new Mercedes-Benz SLR McLaren (due to make its debut in autumn 2003) with the same charismatic qualities.

Just like its legendary predecessor of 1955, this SLR incorporates new technological developments which are ahead of their time. 

For evidence, simply take a glance under the bonnet at the Mercedes-AMG V8 powerplant.

 With its 5.5-litre displacement and screw-type compressor, the engine develops a peak output of 460 kW/626 hp and delivers its maximum torque of 780 Newton metres from 3250 rpm – a figure which remains constant across a broad engine speed range of up to 5000 rpm.

With this kind of power, the SLR McLaren delivers performance figures which are among the best in its class: taking just 3.8 seconds to sprint from 0 to 100 km/h, it passes the 200 km/h mark after 10.6 seconds, and from a standing start it takes just 28.8 seconds to reach 300 km/h. The two-seater has a top speed of 334 km/h (provisional figure).

In the interests of optimum weight distribution, dynamic handling and high stability on braking, the SLR McLaren has a front mid-engined design. The V8 powerplant is mounted on a robust aluminium frame and has a low installation position. Water-type charge-air cooling, three valves per cylinder, dry sump lubrication and four metal catalytic converters are further special features of this powerful engine – an engine which already meets stringent EU 4 exhaust gas regulations which are not due to come into force until 2005

.Three transmission programs for short, sporty gearshifts
The 5-speed automatic transmission, fitted as standard, is also designed for high performance. It allows the driver to choose between three programs, letting him or her determine the shift speed individually.

When "Manual" is selected, the five gears can either be shifted using buttons on the steering wheel or using the selector lever's Touchshift function. In manual mode the driver can select between three shift stages – "Sport", "SuperSport" and "Race" – significantly shortening the shift times still further for an even sportier drive.

High-tech material for exemplary safety and outstanding rigid-ity
The bodyshell of the high-performance sports car is also distinctly high-tech. Along with the front and rear structure and the passenger cell, the swing-wing doors and the bonnet, it is made entirely from carbon fibre composite. The weight advantage of the high-tech material over steel is around 50 percent.

In addition to this, carbon fibres, on impact, are characterised by four to five times higher energy absorption than steel or aluminium. Mercedes-Benz exploits these qualities by inserting two 620-millimetre longitudinal members made from carbon fibre in the front structure of the new SLR. These absorb the entire energy of the crash in a head-on collision without exceeding tolerable deceleration values for the occupants. In an impact the fibres of these elements shred from front to rear with precisely calculated deformation behaviour, ensuring constant deceleration.

This makes the SLR the world's first series-produced car to have a front crash structure made entirely from carbon fibre. The carbon fibre longitudinal members each weigh just 3.4 kilograms.

The passenger cell of the high-performance sports car is also made entirely from this high-tech material. In a head-on, side-on or rear-end collision, it offers the passengers an extremely rigid, safe survival zone. At the rear, two internal longitudinal members made from laminated carbon fibre and a robust cross member take on the task of energy absorption in the event of a crash – as a rule the passenger cell remains structurally unaffected.

Adaptive front airbags which deploy in two stages depending on the severity of the accident, newly developed sidebags which protect the head, plus belt tensioners and belt force limiters all form part of the new SLR's occupant protection system.

Exemplary braking safety
The brake discs of the cutting-edge swing-wing door vehicle are also made from a high-tech material which meets the highest of standards. Here Mercedes-Benz has used carbon fibre-reinforced ceramic to achieve outstanding performance, temperature-resistance and longevity. Thanks to the highly robust material, the SLR's large brake discs allow maximum deceleration of up to 1.3 g – a top value in a series-produced car. At the front axle alone a total brake pad area of 440 cm2 is available.

Further features of the new SLR include Sensotronic Brake Control (the electrohydraulic braking system), the Electronic Stability Program (ESP ®), automatic tyre pressure monitoring, 18-inch wheels and aluminium suspension which bears the signature of experienced race car constructors.