The Mercedes-Benz SL-Class R 230 was presented to the press in the Deichtorhallen in Hamburg in July 2001. A unique combination of state-of-the-art electronic chassis systems guaranteed an exceptional driving experience and outstanding driving safety. It set tones in sports cars and automotive engineering.
At the time of its introduction, the SL 500 was available with an output of 225 kW (306 hp). In the autumn of 2001, the SL 55 AMG with a supercharged V8 and an output of 350 kW (476 hp) was added to the range. In 2002, the SL 350 followed with a 180 kW (245 hp) 3.7-litre V6 engine, and in January 2003 Mercedes-Benz introduced the SL 600 with a 368 kW (500 hp) 5.5-litre V12 twin-turbo engine as the new flagship model.
The SL's extensive range of standard equipment included integral leather seats with a memory function for the electrically adjustable seats and steering wheel, which were also stored on the electronic ignition key, a multi-function steering wheel, automatic air conditioning and stereo car radio.
Innovative driver assistance systems such as the adaptive cruise control DISTRONIC, the automatic emergency call system TELEAID, the control and display system COMAND and the electronic tyre pressure monitor were optionally available.
Leather, exotic wood and aluminium gave the passenger compartment the exclusive and stunning look typical of the SL. Interior furnishings were available in two types of leather, four types of high-quality trims and five colours. The four individual instruments were framed in the SL's classic chronometer cockpit by shiny matt chrome, which was also used to embellish other details in the passenger compartment.
The distinctive details of the R 230 series combined traditional and future design elements. For example, the air inlets in the front wings were a typical feature of the SL 300 in the 1950s. The narrow, wing-like profiles on the side air inlets - referred to by professionals as 'fins'- are reminiscent of the past. The designers used this stylistic element to give the grilles in the bonnet an extra sporty tone.
Another of the SL's distinctive features was its horizontally elongated radiator grille. The R 230 series gave a modern twist to this tradition by reducing the angle of the louvered radiator grille, giving the car's arrow-shaped front a dynamic and powerful look. The four louvers framed the Mercedes star, which was positioned in the familiar spot and left no doubts about the roadster's heritage and affiliation.
These SL-typical features were in perfect harmony with the new elements, such as the headlights, whose familiar oval 'four eyes' now melted into two oval eyes. The modern clear-glass look enhanced the standard Bi-Xenon headlights and added sheen to the front design.
The headlights' oval shape stretched across the elongated bonnet, changing into exciting curves as they progressed. This orchestration of features also gave rise to the design of the muscular wings. The smooth shape of the bonnet flowed seamlessly into sleek lines along the wings, dividing the side of the body at the kerb line. A second line extended from the sweeping shape of the air inlets in the lower section of the wings, giving the large, soft surface of the doors a formal hold and creating an optical link to the boot. The steeply raked windscreen underlined the car's sports character and emphasized the flat, wedge-shaped silhouette.
Unlike its predecessors, the SL-Class R 230 never left its roof behind. The seamless integration of its vario roof into the flowing lines bore testimony to the high quality of the car's design.
The roof opened in 16 seconds by pressing a button or using the remote control. A very complex swivel mechanism guaranteed that the three parts of the roof disappeared into the upper part of the boot. Below the storage space for the roof was a 235-litre luggage compartment. When the roof was closed, the car had a total volume of 317 litres (including the luggage box in the spare wheel well), which was 52 litres more than its predecessor. A version with a glass roof was introduced in 2002.
Other features that emphasized the R 230 series' dynamic and elegant look consisted of the powerful front apron, the body's muscular curves and striking wedge shape, as well as style elements such as the distinctive contours of the side skirts, the wide 17-inch wheels and the oval tailpipes. All of the body parts - from the door handles to the bumpers - were painted in the same colour as the car so that it looked as if the sports car had been made from one mould.
This also applied to the rear of the car with its large, triangular tail lights. No change of colour here, but an elegant unity: The tail lights were protected by evenly coloured red cover glass. A special filter placed in front of the tail-light reflectors guaranteed that the indicator remained yellow and the reverse lights white.
The technical innovations in the R 230 included the electro-hydraulic brakes Sensotronic Brake Control SBCTM, which were introduced with this model. The brakes worked together with the Electronic Stability Programme ESP® and the Active Body Control ABC, which reduced body movements or the first signs of skidding to a minimum in corners and when braking.
The Sensotronic Brake Control SBCTM was also the gateway to the future 'by wire' systems, which transmitted the driver's commands electronically by cable rather than mechanically or hydraulically. The key features of the SBCTM included the very dynamic build up of brake pressure, as well as the intricate sensor technology and reliable 'feel' for the driver's and the vehicle's behaviour.
For example, the system interpreted a quick movement of the driver's foot from the accelerator to the brake pedal as a sign of danger and automatically increased the pressure in the brake lines and placed the brake pads on the brake discs so they could grab the disc without delay and brake at full force as soon as the driver pressed the brake pedal. This shortened the braking distance by three percent in an emergency situation.
The variable brake force distribution, which was based on the vertical force of the wheel and the slip values, enabled the SBCTM to provide even more safety when braking in corners and driving on challenging surfaces. The higher dynamic and precision of the SBCTM also increased the performance of the Brake Assistant BAS and the Electronic Stability Programme ESP®.
This package of very efficient electronic control systems revolutionized automotive engineering in the area of chassis, driving safety and driving dynamics.
These systems were supported by wheel suspensions that responded sensitively in combination with the Active Body Control ABC. At the front, a modern four-bar linkage guaranteed the highest ride comfort, wheel control and steering. The lower front axle elements, the rack and pinion power steering gears and the engine mount were linked by an integral support made of aluminium, which also premiered in the SL.
The still unparalleled multi-link independent rear suspension, including the wheel bearings and the suspension subframe, was made entirely of aluminium for the first time in the SL-Class R 230. The self-steering behaviour was further improved by modifying specific aspects of the suspension geometry.
At the latest since the introduction of the 'Pagoda', the abbreviation 'SL' has been synonymous with pioneering achievements in the areas of active and passive sports car safety. The entirely new holistic safety concept for the SL-Class R 230 clearly outperformed the then current safety standards and became an example of vehicle safety for sports cars in particular. From accident prevention with assistance from electronic drive-dynamic systems such as SBCTM, Active Body Control ABC, Brake Assistant BAS, Traction Control System TCS and ESP® through to the structural safety of the body and the strength of the passenger compartment - the concept took aspects of active and passive vehicle safety for every conceivable type of accident into account.
Occupant safety was guaranteed among other things by the very strong body, two-stage airbags for the driver and front passenger, innovative head-thorax bags in the doors, new integral seats, high-performance belt pre-tensioners, belt load limiters and the sensor-controlled roll-over bar that also activated when the vario roof was closed.
Mercedes-Benz's in-house developed emergency call system TELEAID (optional) automatically notified emergency services and the police and guided them to the site of the collision by satellite.
The SL-Class R 230 passed the strictest crash tests, such as the frontal impact test, at 64 km/h, and the 90‑degree side impact test at 50 km/h, both of which are part of the European New Car Assessment Programme (NCAP) and had strict body requirements especially for open-top cars. The engineers dedicated the same amount of attention to repair friendliness, which they assessed at a front and rear impact speed of 15 km/h. The SL's body structure provided the highest level of occupant safety and met the objective of low-cost repair.
Thanks to its numerous innovations, the SL's body structure provided the highest level of occupant protection in the event of a front or rear impact at a collision speed of 15 km/h. Some 30% of the bodyshell was made of high-tensile sheet metal that combined maximum resistance with minimum material thickness. All of the components that were key for crash safety and body stiffness were made of sheet steel. The fuel tank was made of sheet steel and was in a protected location above the rear axle.
The fuel economy of the SL-Class R 230 was discussed virtually throughout the design specifications. The body's light weight played a major role in all of the versions' favourable fuel economy: Bonnet, front wings, doors, boot lid, tank partition and other components were made of aluminium, but the approximately 1.40 m long bonnet was considered the star among the lightweight components.
The sophisticated aerodynamics of the smooth, streamlined body and underbody also contributed to the car's fuel economy and helped minimize noise. The drag coefficient (cd) of 0.29 for the closed car was exceptional; the R 129 predecessor with hard-top had a cd of 0.32. The open SL-Class R 230 had a cd of just 0.34 (R 129: cd of 0.40 with closed side windows).
In the summer of 2001, the SL 500 was introduced with a 5‑litre V8 engine (M 113) with an output of 225 kW (306 hp) and a torque of 460 Nm. It was one of the most powerful engines in its vehicle class, clearly undercut the strict Euro-4 emission standards and accelerated from 0 to 100 km/h in 6.3 seconds. The car achieved a top speed of 250 km/h (electronically limited). The proven 5-speed automatic transmission with electronic controls, two shifting programmes and torque converter lockup clutch were part of the SL 500's standard equipment. A brand new touch shift enabled rapid manual gear shifting.
The SL 55 AMG was unveiled at the International Motor Show (IAA) in Frankfurt/Main in September 2001. Equipped with a new V8 supercharged engine, it was Mercedes-Benz's most powerful automobile: The 5.5-litre engine (M 113) developed an output of 350 kW (476 hp) and provided a constant torque that reached its peak of 700 Nm between 2650 rpm and 4500 rpm. The vehicle accelerated from 0 to 100 km/h in 4.7 seconds and the electronically limited maximum speed was 250 km/h. The engine was combined with a 5-speed automatic transmission that included paddle-driven steering-column gear changing.
The exterior of the SL 500 distinguished itself from the AMG by its more powerfully styled bumpers, distinctive side skirts, clouded tail lights, exclusive 18-inch multi-spoke wheels and four chromed exhaust pipes.
The character of the sports car's passenger compartment was emphasized by the more tightly upholstered integral seats with special perforation and coloured decorative stitching, trims made of high-quality sand-cast aluminium and cockpit instruments with light faces, silver gauges and red needles.
2002 saw the introduction of the SL 350 whose powerful 180 kW (245 hp), 3.7-litre V6 engine (M 112) accelerated the car from 0 to 100 km/h in 7.2 seconds and enabled it to reach an electronically limited maximum speed of 250 km/h. The car was equipped with the 6-speed automatic transmission SEQUENTRONIC, which was controlled by two levers on the steering column. The electronically controlled 5-speed automatic transmission with touch shift was optionally available.
In January 2003, Mercedes-Benz introduced the SL 600 with a 368 kW (500 hp), 5.5-litre V12 twin-turbo engine (M 275) as the new top-of-the-range model. It had an incredible maximum torque of 800 Nm that was available as early as 1800 rpm and remained constant at 3600 rpm. The new twelve-cylinder powertrain with two turbo chargers, water intercooling, three-valve technology, twin-spark AC ignition and other high-tech innovations made this one of the most innovative automobile engines in the world. It offered sophistication in every driving situation. The SL 600 accelerated from 0 to 100 km/h in just 4.7 seconds. Its maximum speed was electronically limited to 250 km/h.
The exterior of the SL 600 was distinguished by a radiator grille with subtle chrome elements, silver brake callipers, the V12 emblem on the side air intakes, Bi-Xenon headlights and exclusive light-alloy wheels. The front axle was equipped with 255/40 R 18 tyres and the rear axle with 285/35 R 18.
In June 2003, Mercedes‑Benz introduced the legendary 'Mille Miglia Edition 2003', which was based on the SL 350 and conjured up memories of the famous open-road endurance race: Only 12 were made. They were painted in a special 'Silver Arrow' metallic paint and had matt-shiny kerb-line aluminium trims, elegant 18-inch light-alloy wheels, 255/40 ZR 18 wide-base tyres (front) and 285/35 ZR 18 (rear) as well as 'Mille Miglia' insignia in the ventilation louvers in the front wing and the boot lid.
The vario roof on the special model was made of glass, enabling passengers to enjoy a panoramic view. Two-tone Napa leather finishing gave the interior a special touch: The seats were ‘classic red', a colour that had already attracted attention in the legendary 1950s SL sports car. The roof was lined with soft Alcantara, and the matt-shiny trims in the centre console and the doors were aluminium. The designers used new laser technology to apply the 'Mille Miglia' logo and the route of the 1000‑mile race to the leather head restraint.
Additional standard equipment included the control and display system COMAND, the parking assist system PARKTRONIC, multi-contour backrests, a CD changer and sound system. The V6 engine is coupled with a 5-speed automatic transmission.
In 2004, Mercedes-Benz celebrated the introduction of the SL 300 in 1954 with a special 'Edition 50' model of which 500 models were available as SL 350 and SL 500. The optical highlights included the silver-matt radiator grille with chrome trims, the 18-inch turbine light-alloy wheels, the highly polished kerb-line trims, the wind deflector with highly polished frames and the smoked tail lights.
The instrument cluster was finished in a combination of leather and Alcantara. The climate controlled multi-contour seats were covered with Napa leather and the 'Edition 50' logo was lasered in the head restraints. The interior trims were available in aluminium or black ash. The finishing was optionally available in condor silver/black two-tone leather or in plain designo black leather with decorative quartz stitching. The extensive standard equipment package also included the radio/navigation system with CD changer and surround sound system COMAND APS, Bi-Xenon headlights with headlight washing system and the parking assist system PARKTRONIC