The Mercedes-Benz SLR McLaren (C199 / R199 / Z199) is a grand tourer jointly developed by German automotive manufacturer Mercedes-Benz and British automobile manufacturer McLaren Automotive and sold from 2003 to 2010. When the car was developed, Mercedes-Benz owned 40 percent of the McLaren Group and the car was produced in conjunction between the two companies.
SLR is an abbreviation for "Sport Leicht Rennsport" (Sport Light Racing), a homage to the Mercedes-Benz 300 SLR which served as the car's inspiration. The car was offered in coupé, roadster and speedster bodystyles with the latter being a limited edition model.
The SLR was succeeded by the SLS AMG in 2010.
At the 1999 North American International Auto Show, Mercedes-Benz presented their Vision SLR concept, inspired both by the Mercedes-Benz 300 SLR Uhlenhaut Coupé of 1955, which was a modified Mercedes-Benz W196S race car, and the design of closed-wheel Formula One cars, a field in which Mercedes had prior experience, as Mercedes-Benz were already designing and developing powertrains and electronics for McLaren's Formula One Team. The car was presented as "Tomorrow Silver Arrow" in a clear reference to the Silver Arrows of the golden age of Mercedes in competition during the fifties. Later that year, during the Frankfurt Motor Show, a roadster version of the SLR concept was presented. The concept car was fitted with a 5.0-litre supercharged AMG V8 engine able to generate a power output of 565 PS (416 kW; 557 hp) and 720 N⋅m (531 lb⋅ft) of torque at 4,000 rpm, mated to a 5-speed automatic gearbox with Touchshift control.
Wanting to bring the concept to production following its positive reception, Mercedes joined forces with their Formula One partner, McLaren, thus creating the Mercedes-Benz SLR McLaren. The production version of the car was unveiled to the general public on 17 November 2003 having some minor design adjustments in respect of the initial design. The adjustments included more complex vents on both sides of the car, a redesigned front with the three pointed star plunged in the nose and red tinted rear lights.
The Mercedes-Benz SLR McLaren saw a production run of over six years. On 4 April 2008, Mercedes announced it would discontinue the SLR. The last of the coupés rolled off the production line at the end of 2009 and the roadster version was dropped in early 2010.
Due to the automatic gear box, front mid-engine arrangement, and its driving characteristics, some automotive journalists classify the SLR McLaren as a grand tourer, whose rivals would include automobiles such as the Aston Martin DBS V12 and the Ferrari 599 GTB Fiorano.
The SLR features Sensotronic Brake Control, a type of brake-by-wire system. The brake discs are carbon-ceramic units and provide better stopping power and fade resistance than steel discs when operating under ideal working temperature. Mercedes-Benz claims these discs are fade resistant to 1,200 °C (2,200 °F). The front discs are internally vented and measure 370 mm (14.6 in) in diameter; eight-piston callipers are used. Rear discs are 360 mm (14.2 in) in diameter with four-piston callipers. During wet conditions the callipers automatically skim the surface of the discs to keep them dry.
The SLR features active aerodynamics; there is a spoiler mounted on the rear integral air brake flap. The spoiler increases downforce depending on its angle of elevation (angle of attack). At a set speed, the spoiler/brake automatically raises to 10 degrees (15 degrees in the 722 edition), when demanded via the driver's switch, the elevation can be increased to 30 degrees (35 degrees in the 722 edition) for increased rear downforce, at the cost of increased steady state drag. The car has a flat underbody and a rear diffuser for improved downforce. Due to this, there was no other place for the exhaust pipes to exit, other than the sides of the car, making it another unique feature of the SLR.
The SLR has a 232 kg (511 lb) hand-built 5.4 L; 331.9 cu in (5,439 cc) supercharged all-aluminium alloy, SOHC 3 valves per cylinder 90° V8 engine, with a bore X stroke of 97 mm × 92 mm (3.82 in × 3.62 in) and with a compression ratio of 8.8:1. The engine is lubricated via a dry sump system. The Lysholm-type twin-screw supercharger rotates at a maximum of 23,000 rpm and produces 0.9 bar (13 psi) of boost. The compressed air is then cooled via two intercoolers. The engine generates a maximum power output of 626 PS (460 kW; 617 hp) at 6,500 rpm and maximum torque of 780 N⋅m (575 lbf⋅ft) between 3,250 to 5,000 rpm.
McLaren took the original concept car designed by Mercedes and moved the engine 1 metre (39.4 in) behind the front bumper, and around 50 centimetres (19.7 in) behind the front axle. They also optimised the design of the centre firewall.
The SLR uses the AMG SPEEDSHIFT R five-speed automatic transmission with three manual modes. For durability, Mercedes selected a five-speed transmission rather than their seven-speed transmission which was more complex and used more parts.
The car uses carbon-fibre reinforced plastic (CFRP) construction in an attempt to keep the weight low. Despite CFRP materials, the total curb weight is 1,750 kg (3,858 lb). The SLR could attain a top speed of 334 km/h (208 mph).
Road And Track tested the car in their July 2005 Road Test and reached 97 km/h (60 mph) from a standstill in 3.5 seconds. The 0 to 161 km/h (100 mph) sprint was achieved in 7.5 seconds and a 1⁄4 mile (402 m) run was completed in 11.5 seconds at 203 km/h (126 mph).
A new version of the SLR was introduced in 2006, called the Mercedes-Benz SLR McLaren 722 Edition. The "722" refers to the victory by Stirling Moss and his co-driver Denis Jenkinson in a Mercedes-Benz 300 SLR with the starting number 722 (indicating a start time of 7:22 a.m.) at the Mille Miglia in 1955.
The "722 Edition" includes a modified version of the engine used in the SLR generating a power output of 650 PS (478 kW; 641 hp) at 6,500 rpm and 820 N⋅m (605 lb⋅ft) at 4,000 rpm. 19-inch light-alloy wheels were used to reduce unsprung mass, while modifications were also made to the suspension, with a stiffer damper setup and 10 mm (0.39 in) lower ride height introduced for improved handling. Larger 390 mm (15.4 in) diameter front brakes and a revised front air dam and rear diffuser were fitted.
Other exterior changes include red "722" badging, harking back to the original 722 racer, black tinted tail lights and headlamps. The interior has carbon fibre trim and black leather upholstery combined with Alcantara.
The SLR 722 can accelerate from 0 to 100 km/h (62 mph) in 3.6 seconds, 0 to 200 km/h (124 mph) in 10.2 seconds and 300 km/h (186 mph) in 27.6 seconds, and can attain a top speed of 337 km/h (209 mph), faster than the standard Mercedes-Benz SLR McLaren.
A roadster version of the SLR went on sale in September 2007. It uses the same engine as its coupé sibling, generating a power output of 626 PS (460 kW; 617 hp), to propel it to a top speed of 334 km/h (208 mph) and a 0 to 100 km/h (62 mph) acceleration time of 3.6 seconds.
However, as a convertible, the roadster was burdened with extra weight, which affected performance and handling. The Roadster's roof is made from a "newly developed material" and does not take the form of a folding metal arrangement, as is common on many modern cars. Following a manual unlatching, it takes ten seconds to fold away electrically. According to an official Mercedes document, the cabin of the roadster is capable of allowing conversation between driver and passenger up to a speed of 200 km/h (124 mph) with the roof retracted. The SLR Roadster was aimed to compete against other luxurious sports cars such as the Pagani Zonda F Roadster.
The Roadster variant of the 722 Edition was unveiled at the 2007 Frankfurt Motor Show. The roadster has the same engine and suspension setup as the coupé along with the folding roof mechanism shared with the standard SLR roadster. It can accelerate from 100 km/h (62 mph) from standstill in 3.1 seconds and has top speed of 334 km/h (208 mph).
The model went on sale in January 2009 and production was limited to 150 units.
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