Mercedes-Benz SLR McLaren
| Mercedes-Benz SLR McLaren | |
|---|---|
 | |
| Overview | |
| Manufacturer | Mercedes-Benz |
| Production | 2003-present (3,500 to be produced) |
| Body and chassis | |
| Class | Supercar/grand tourer |
| Body style | 2-door coupé 2-door roadster |
| Layout | FMR |
| Powertrain | |
| Engine | 5.5 L supercharged V8 |
| Transmission | 5-speed semi-automatic |
| Dimensions | |
| Wheelbase | 2700 mm (106.3 in) |
| Length | 4656 mm (183.3 in) |
| Width | 1908 mm (75.1 in) |
| Height | 1261 mm (49.6 in) |
| Curb weight | 1768 kg (3898 lb) |
The Mercedes-Benz SLR McLaren is a German supercar jointly developed by Mercedes-Benz and McLaren Automotive. It is assembled at the McLaren Technology Centre in Woking, England. DaimlerChrysler owns 40% of the McLaren Group.
Classified as a supercar and compared to cars like the Porsche Carrera GT and Ferrari Enzo, the presence of the automatic gear box, front mid-engined arrangement and its driving characteristics lead some commentators to classify the SLR McLaren as a Super GT whose closer rivals are the Aston Martin Vanquish and Ferrari 599 GTB. One of the goals of the SLR was to combine both supercar and GT characteristics.[1]
It is the fastest automatic transmission car in the world. SLR stands for "Sport, Leicht, Rennsport" (sport, light, racing). Mercedes-Benz has stated that they will build 3500 SLRs in a span of 7 years, with an annual production of only 500 cars.[2] The car's base price is £300,000 or $ 404,234. (17/08/07 exchange).
History
The Mercedes-Benz SLR McLaren is inspired by the Mercedes-Benz 300 SLR of 1955 which was actually based on the W196 F1 car, yet named after the road-going Mercedes 300SL Gullwing.
Overview
Brakes
The brake discs are carbon-ceramic which provide better stopping power and fade resistance than steel discs. Mercedes-Benz claims these discs are fade resistant to 1000 °C. The front discs are internally vented and 370 mm in diameter. 8 piston calipers are used. Rear discs are 360 mm in diameter with 4 piston calipers. The result of these massive rotors is a maximum braking power of 1500 kW. When it is wet the calipers automatically skim the surface of the disks to keep them dry.
The SLR also has a spoiler mounted on the rear integral air brake flap. The spoiler increases downforce depending on its angle of elevation (angle of attack). At speeds above 95 km/h the spoiler/brake automatically raises to 10 degrees (15 in 722 edition), when demanded via the driver's switch, the elevation can be increased to 30 degrees (35 in 722 version) for increased rear downforce, at the cost of increased steady state drag. A final function is the automatic air brake, when engaged the rear elevation angle is increased to 65 degrees. The additional rear downforce in addition to the markedly increased aerodynamic drag increases peak deceleration ~25%.
Engine
The SLR Mclaren sports a 232-kilogram (511.8 lb), hand-built, 5.4-litre (5439 cc/331.9 cu in), supercharged, all-aluminum, SOHC V8 engine. The cylinders are angled at 90 degrees with three valves per cylinder and lubricated via a dry sump system. The compression ratio is 8.8:1 and the bore and stroke is 97 milimetre (3.82 in) and 92 milimetre (3.62 in), respectively. The Lysholm-type twin-screw supercharger produces 0.9 bar (13 psi) of boost, the turbine rotates at 23000 revolutions per minute, and the air is cooled via two intercoolers. The engine generates a maximum power of 626 PS (617 hp/460 kW) at 6500 revolutions per minute and a maximum torque of 780 newton-metre (575 lb·ft) at 3250 revolutions per minute.
Unlike most of its contemporaries, its engine is front-mid mounted. McLaren took the original concept car designed by Mercedes and moved the engine 1 metre behind the front bumper, and around 50 cm behind the front axle. They also optimised the design of the centre firewall.
Transmission
The SLR has a five speed automatic transmission with three separate modes: Sport, Comfort and Manual.[3] Sport is designed for everyday use; Comfort starts in second gear for smoother ride quality and inclement weather. Manual allows the driver to shift gears with the manumatic gear lever or the buttons (stock SLR) / paddles (722) attached behind the steering wheel. When in Manual, three additional modes (Sport, Supersport, Race) on the second dial can be used, each significantly making quicker shift times. This is the same transmission as used in other performance models such as the SL65 AMG. The Mercedes-Benz seven speed automatic transmission as used on the SLK 55 AMG cannot handle power and torque output of the SLR, S65 AMG, SL65 AMG, CL65 AMG; hence it is fitted with only a five speed transmission.
| Gear | 1 | 2 | 3 | 4 | 5 | Final Drive |
|---|---|---|---|---|---|---|
| Ratio | 3.56:1 | 2.19:1 | 1.41:1 | 1.00:1 | 0.83:1 | 3.06:1 |
Performance
Mercedes-Benz's performance claims for the SLR have been confirmed. Depending on the source, the car accelerates from 0 to 100 km/h in approximately 3.5 seconds (see below), 0-200 km/h in 10.6 seconds, and 300 km/h in 28.8 seconds, and has a top speed of 334 km/h (207 mph), and has once reached a speed of 210 mi:h[convert: unknown unit], which makes it the fastest car with a true automatic transmission with a torque converter. The car uses carbon fibre for its entire body construction, which makes it lighter. Kerb weight is 1768 kg (3898 lb). The SLR is one of the safest and most luxurious supercars ever built, straying from the common supercar practice of eliminating luxuries for the sake of weight reduction.
Car and Driver achieved a 0-60 time of 3.6 seconds, and a quarter-mile time of 11.6 seconds at 125 mi:h[convert: unknown unit]. C&D suggests the times may be even lower if temperatures were higher. Car and Driver achieved top gear acceleration 30-50 mph and 50-70 mph times of 1.7 and 2.4 seconds, which are the fastest ever recorded by the magazine in a production car. The SLR also pulled 0.97 g on the skidpad.
Road and Track tested the car in their July 2005 Road Test and got 60 mi:h[convert: unknown unit] from a standstill in 3.5 seconds. The 0-100 mph sprint was achieved in 7.5 seconds and a Quarter Mile run was completed in 11.5 seconds at 126 mi:h[convert: unknown unit].
The German magazine Auto Motor und Sport, in 2004, tested the SLR at the Nardo test track in southern Italy. They reported that the SLR accelerates from 0 to 100 km/h in 3.8 seconds, 200 km/h in 10.7 seconds, and 300 km/h in 30.6 seconds. The car's 400-meter time and 1 km time were found to be 11.5 seconds at 207 km/h, and 20.5 seconds at 269 km/h, respectively. They also reached it's claimed 334 km/h topspeed.
Comparison
Despite its 2-ton weight, the fuel economy is generally better than the lighter Lamborghini Murciélago, and even its lighter, less expensive, less powerful sibling, Gallardo.[4] Also, BBC auto show Top Gear put the SLR and the Porsche Carrera GT on its track, and the Porsche beat the SLR-Mclaren by just over a second (1:19.8 vs. 1:20.9 [1]). However, on a separate race around the same track, the SLR was fractionally quicker than the Carrera GT. In a straight line, the SLR is quicker throughout the range.
722 Edition
A new version 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" creates 650 bhp, with a top speed of 332 km/h (5 more than the standard SLR). A new suspension is used with 19-inch light-alloy wheels, a stiffer damper configuration and 0.4 inches lower body.
Power is boosted to 478 kW (650 hp) and 820 N·m (605 ft·lbf) torque at 4000 rpm. Modifications were also made to the suspension, with a stiffer damper setup and 10 mm (0.4 in) lower ride height introduced for improved handling. Larger 390 mm diameter front brakes and a revised front air dam and rear diffuser were fitted.[5]
Overall performance has increased, with a claimed 0-100 km/h time of 3.6 seconds, 0-200 km/h time of 10.2 seconds and 0-300 km/h in 28 seconds.
Exterior changes included larger 19-inch black alloy wheels and red 722 badging (harkening back to the original 722 racer).
Roadster
A roadster version of the SLR has also been confirmed, due to go on sale in September 2007 for £350,000. It uses the same supercharged V8 AMG power plant as its coupé siblings, developing 626 bhp, to propel it to a top speed of 332 km/h and enable a 0-62 mph (0-100km/h) dash time of 3.8 seconds. However, being a convertible the roadster will have to be burdened with extra weight and this will affect performance and handling. The Roadster's roof, however, is made from a "newly developed material" and hence will not take the form of a folding metal arrangement, as is now common on many modern cars. Following a manual unlatching, it takes a mere 10 seconds to fold away electrically. It is unsure if Mclaren will release another version of the roadster like it did with the SLR 722 version. This roadster is aimed to compete against other hypercars such as the Pagani Zonda F Roadster.[6]
References
- "McLaren Automotive: Mercedes-Benz SLR McLaren". Retrieved 2007-06-25.
- Grabianowski, Ed. "Howstuffworks "How the Mercedes SLR Works"". Retrieved 2007-06-25.
Notes
- ^ Harvey, Michael (2005). "Yahho Cars: Mercedes SLR McLaren". Yahoo Cars (UK). Retrieved 2007-07-10.
- ^ "1000th 'modern Silver Arrow' from McLaren". motoring.co.za. Retrieved 2007-07-10.
- ^ Winfield, Barry (February 2004). "2005 Mercedes-Benz SLR McLaren". Car and Driver. pp. pp. 1-2. Retrieved 2007-06-25.
{{cite web}}:|pages=has extra text (help) - ^ "Yahoo Autos: Side by Side Comparison". Yahoo! Autos. Retrieved 2007-07-10.
- ^ Nunez, Alex (2006-07-10). "Mercedes-Benz SLR 722 boosts performance, honors past". Autoblog. Retrieved 2007-07-10.
- ^ "Goodwood Goodies: SLR McLaren Roadster". Edmunds. 2007-06-20. Retrieved 2007-06-25.
External links
- SLR McLaren official microsite.
- McLaren Automotive's SLR McLaren web page.
- Lysholm Technologies AB, manufacturer of the SLR McLaren's supercharger.