AIR CONDITIONING EXPANSION VALVE

The Mercedes-Benz SLR McLaren is an Anglo-German supercar jointly developed by Mercedes-Benz and McLaren Automotive, built in Portsmouth and the McLaren Technology Centre in Woking, Surrey, England. At the time Mercedes-Benz owned 40 percent of the McLaren Group.
Due to the presence of the automatic gear box, front mid-engined arrangement, and its driving characteristics, some commentators classify the SLR McLaren as a GT whose rivals would be vehicles like the Aston Martin DBS V12 and Ferrari 599 GTB Fiorano.
SLR stands for "Sport, Leicht, Rennsport" (sport, light, racing). Mercedes-Benz stated that they would build 3,500 SLRs over a span of seven years, with an annual production of 500 cars. The car's base price is GBŁ300,000 (approx. US$495,000 or €346,000, c. 2009).[
The Mercedes-Benz SLR McLaren was inspired by the Mercedes-Benz 300 SLR of 1955, based on the W196 F1 car, yet named after the road-going 300SL Gullwing. On 4 April 2008, Mercedes announced they would cease production of the SLR. The last of the coupes rolled off the production line at the end of 2007 and the roadster version was discontinued in early 2009.
Brakes
The SLR features Sensotronic, a type of brake-by-wire system. The brake discs are carbon-ceramic (in the front only) 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 370 mm (15 in) in diameter. 8 piston calipers are used. Rear discs are 360 mm (14 in) in diameter with 4 piston calipers. During wet conditions the calipers automatically skim the surface of the discs to keep them dry.
To improve braking performance there is an automatic air brake, when engaged the rear elevation angle of the rear spoiler is set to 65 degrees. The additional rear downforce in addition to the markedly increased aerodynamic drag increases peak deceleration ~90%.
Aerodynamics
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 speeds above 95 km/h (59 mph) 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, also when the driver applies the brakes spoiler raises.
Engine
The SLR sports a 232 kg (510 lb) hand-built 5,439 cc (5.439 L; 331.9 cu in), supercharged, all-aluminium, 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 millimetre (3.82 in) and 92 millimeters (3.62 in), respectively. The Lysholm-type twin-screw supercharger rotates at 23000 revolutions per minute and produces 0.9 bar (13 psi) of boost. The compressed air is then cooled via two intercoolers. The engine generates a maximum power of 626 PS (460 kW; 617 hp)@6500rpm and maximum torque of 780 N·m (580 lb·ft)@3250-5000rpm.
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 (39.4 in) behind the front bumper, and around 50 centimetres (19.7 in) behind the front axle. They also optimized the design of the center firewall.
Transmission
The SLR uses AMG SPEEDSHIFT R 5-speed automatic transmission with 3 manual modes. For durability Mercedes selected a 5-speed transmission rather than their 7-speed gearbox which was more complex and used more parts.
Performance
The car uses carbon fibre for its entire body construction in an attempt to keep the weight low. Despite CFRP materials the total curb weight is 1,768 kg (3,898 lb). The following tests have proven that the SLR can achieve a 0-100 km/h (62 mph) in times less than the claimed 3.7 seconds and reach a top speed of 334 km/h (208 mph)[5].
In June 2004 the SLR was tested at Nardo and performed the 0-100 km/h (62 mph) exercise in 3.8 seconds, 0-200 km/h (124 mph) in 10.3 seconds and 0-300 km/h (190 mph) in 30.4 seconds.Their 400 metre and kilometre times were 11.4 seconds at 128 mph (206 km/h) and 20.6 seconds at 270 km/h (170 mph) respectively. They also reached its claimed topspeed 365 km/h (227 mph).

Our right front tire was low, so we stopped at Certified to get air. They charge $1 for it! However, the pump was pretty cool; you have only to set it to the desired PSI and the machine stops when it's reached. The compressor doesn't start until you have the nozzle on the valve stem. It sure beats having to stop and check repeatedly as you fill each tire.