Technological innovations mark next generation Mercedes-Benz SL
On Tuesday, July 31, Mercedes-Benz unveiled the next generation SL at the Deichtorhallen exhibition centre in Hamburg, Germany. The SL 500 will go on sale in Canada in the Spring of 2002 as a 2003 model. Pricing has not yet been announced.
The new open-top two-seater is the fifth generation of the Mercedes SL series, a series which began in 1954 with the legendary "gullwing-door" 300 SL. Since then, Mercedes-Benz has produced some 490,000 of these exclusive sports cars.
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Design of the new SL 500 began in 1996 when a design team of ten young men and women from Germany, California and Japan were selected to take on the task of shaping the new Mercedes Roadster. The result is an automobile filled with technological innovation, but one that also pays tribute to its historical roots.
Building on tradition, the designers pay homage to the car's legendary past with striking stylistic details, such as the air inlets behind the front wheels, which are characteristic of the 300 SL from the 1950s and the elongated radiator grille, a traditional SL styling element modernized with the grille slats pointing into the air stream at a much flatter angle than has previously been the case.
Complementing these classic SL features are sophisticated elements which take the Mercedes sports car far into the future. The headlamps are one example. The familiar "four-eyed" pattern remains, but with the two "eyes" on each side melting into one another. A circular Fresnel lens projects from the centre of a perforated chromed plate, concentrating the light emitted by the standard-fitted xenon headlamps.
Like the front headlamps, the rear lights of the new SL-Class are also technologically advanced. The all-red coloured covers conceal up to seven different light functions: brake lights, taillights, fog light (left only), indicator lights, reflectors and reversing lights. Mercedes engineers have developed special filter discs to ensure that the indicator and reversing lights show yellow and white respectively despite the red colour of the covers. These discs are located on the inside of the covers – a turquoise filter for the reversing light and a yellow filter for the indicator.
The SL 500's vario-roof, a folding hardtop which was introduced in 1996 in the SLK-Roadster, turns the two-seater from an open-air summer roadster into an all seasons coupe at the touch of a button. The new SL needs only around 16 seconds to complete the transformation from coupe to roadster (or vice versa) – in the SLK this process takes 25 seconds.
Care was taken to preserve luggage space in the trunk with the roof open. Cargo capacity in the SL is 235 litres when the vario-roof is open – sufficient space for the luggage of most occupants. The vario-roof takes up only about one third of the 317 litres of capacity when the roof is up. The folded roof can be raised automatically about 20 degrees, making the items of luggage stowed underneath easily reachable. When the luggage cover is closed again, the roof is lowered back down.
The engineers at the Mercedes-Benz production facility in Sindelfingen, Germany, came up with a series of construction measures to give the SL 500 high levels of rigidity and solidity even when the roof is open. They relied largely on high-strength steels. In addition to aluminium, some 33 percent of the SL body shell is made of high-strength steel – up from 19 percent in the predecessor model. All the key components in terms of the crash safety and body shell rigidity of the new SL have been made of high-strength steel.
Other features optimising torsional rigidity include:
A multi-piece floor system with engine tunnel and reinforced tunnel bridge
Steel panels under the seats with lateral and transverse stiffening
A dual-shell cross member located below the front windscreen
A cross member profile fixed under the instrument panel
High-strength steel side members
Dual-shell A-pillars with high-strength steel tubes
Large and strong steel reinforcements in the lower B-pillars
A robust high-strength cross member located behind the seats
An aluminium partition wall behind the fuel tank
A steel spare wheel well
Diagonal struts between the sub-frame and forward section of the side member and in the rear between the spare wheel well and the rear section of the side member
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The static torsional flexing of the new SL body is only 3.37 millimetres per metre when the vario-roof is open - over 20 percent lower than that of its predecessor model. The differences are even greater when it comes to the static flexing of the engine tunnel and side member.
The new SL 500 is 36 mm longer than its predecessor (4535 mm), 6 mm wider (1815 mm), 8 mm higher (1298 mm) and has a wheel base that is 45 mm longer (2560 mm). Despite its larger size and greater use of high strength steel, the new SL weighs the same as its predecessor (1845 kg).
The new SL 500's power plant is an all-aluminum 5 litre (4966 cu cm) V-8 producing 306 horsepower at 5600 rpm. Mercedes-Benz estimates the two-seater accelerates from 0 to 100 km/h in 6.3 seconds and covers the burst from 60 to 120 km/h in third gear within 7.6 seconds.
The electronically-controlled five-speed automatic transmission can be shifted manually.
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The 2003 SL 500 introduces Sensotronic Brake Control (SBC) – an electro-hydraulic braking system - essentially a "brake by wire" system. This technology communicates the driver's commands electronically via cable, rather than mechanically or hydraulically, as has traditionally been the case. If the driver switches his foot quickly from accelerator to brake pedal, SBC recognises the early signs of an emergency situation. The system automatically raises the pressure in the brake lines and instantaneously presses the pads onto the brake discs. This system can reduce emergency stopping distances by up to three percent.
The 2003 SL 500 has numerous high tech standard features designed to improve vehicle handling and safety. Among these are:
Active Body Control: using high-pressure hydraulics, the system adapts the damping of the car body to the current driving situation. ABC also takes into account the current vehicle weight for the very first time.
Airbags with two-stage gas generators: front airbags inflate variably in 2 stages according to crash severity.
Roll-over bar: in the event of a crash, special sensors ensure that the roll-over bar is in position immediately.
Head-thorax bags in the doors: the new air cushions reduce the risk of injury in the event of a side-on crash.
ESP: the electronic stability program works in tandem with SBC, even faster and more precisely than before.
Belt tensioner and belt force limiter: these Mercedes developments complement the occupant protection system
Xenon headlamps: gas discharge headlamps produce a beam twice as strong as that of halogen headlamps. Optional: bixenon headlamps for high and low beam.
Automatic climate control: sensors detect the sun's intensity, the air quality and the humidity, enabling the system to work highly efficiently.
LEDs in all brake lights: LEDs are more eye-catching and therefore improve safety.
Memory function (key-operated): each of the two electronic keys can be used to store individual seat, mirror and steering wheel positions.
Central locking: the glove compartment, the stowage compartment between the seats and the stowage boxes in the rear are also locked automatically.
Adaptive accelerator: the engine characteristics adapt to suit a personal driving style.
ELCODE: the vario-roof can also be remotely opened or closed using the electronic key.
Multi-function steering wheel: the driver can operate the car radio, phone and other functions from the steering wheel.
Touchshift: the automatic drive ranges can be selected by nudging the selector lever.
Optional features include:
COMAND: car radio, CD player, TV unit, navigation system and telephone controls all-in-one.
DISTRONIC: the autonomous intelligent cruise control keeps the SL at a safe distance from the vehicle in front and relieves driver stress.
Tire pressure monitor: the tire inflation pressure is checked automatically.
LINGUATRONIC: car radio and car phone with voice-operated control.
TELEAID: following an accident, the system automatically sends an emergency call signal by mobile phone.
Sound system: when playing back music, the system adapts the frequency and audio settings to suit the level of driving noise.
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Interior space has been increased in the new SL roadster with more interior length, head room and shoulder room. The front to back travel of the seats has been increased by 50 mm, while their vertical movement has been increased 30 mm.
So that both driver and passenger can make themselves as comfortable as possible, the integral seats - components of the seat belt system are located within the seat itself - feature stepless power adjustment of seat height, fore/aft position, seat cushion angle and length, electrical headrest and backrest adjustment plus lumbar supports in the seat backrest. This last setting is made by means of an individually adjustable air chamber fitted to each seat, linked to a pressure governor located in the trim panel at the bottom of the seat.
Leather, fine wood and aluminium are used to guarantee classic SL exclusivity and quality in the interior.Mercedes customers can chose from two types of leather, high-quality trim finishes in burr walnut, chestnut, black ash or aluminium and five interior colours. There is a choice of either subtle tone contrasts or striking colour combinations. With the 14 exterior paint colours, this gives customers of the new SL-Class a total of 46 different possibilities when planning the colour scheme of their sports car.
