Monday, January 17, 2011

McLaren F1, 1993

McLaren F1, 1993

 
 

The McLaren F1 is a sports car designed and manufactured by Gordon Murray and McLaren Automotive. On March 31, 1998, it set the record for the fastest production car in the world, 240 mph (391 km/h). As of April 2009, the McLaren F1 is succeeded by three faster cars in sheer top speed, but is still the fastest naturally aspirated production car.

The car features numerous proprietary designs and technologies. It is lighter and has a more streamlined structure than even most of its modern rivals and competitors despite having one seat more than most similar sports cars, with the driver's seat located in the middle. It features a powerful engine and is somewhat track oriented, but not to the degree that it compromises everyday usability and comfort. It was conceived as an exercise in creating what its designers hoped would be considered the ultimate road car. Despite not having been designed as a track machine, a modified race car edition of the vehicle won several races, including the 24 Hours of Le Mans in 1995, where it faced purpose-built prototype race cars. Production began in 1992 and ended in 1998. In all, 106 cars were manufactured, with some variations in the design.

The idea was first conceived when Murray was waiting for a flight home from the fateful Italian Grand Prix in 1988; Murray drew a sketch of a three seater sports car and proposed it to Ron Dennis, pitched as the idea of creating the ultimate road car, a concept that would be heavily influenced by the Formula One experience and technology of the company and thus reflect that skill and knowledge through the McLaren F1.

The car was first unveiled at a launch show, 28 May 1991, at The Sporting Club in Monaco. The production version remained the same as the original prototype (XP1) except for the wing mirror which, on the XP1, was mounted at the top of the A-pillar. This car was deemed not road legal as it had no indicators at the front; McLaren was forced to make changes on the car as a result (some cars, including Ralph Lauren's, were sent back to McLaren and fitted with the prototype mirrors). The original wing mirrors also incorporated a pair of indicators which other car manufacturers would adopt several years later.

Engine

Gordon Murray insisted that the engine for this car be naturally aspirated to increase reliability and driver control. Turbochargers and superchargers increase power but they increase complexity and can decrease reliability as well as introducing an additional aspect of latency and loss of feedback, the ability of the driver to maintain maximum control of the engine is thus decreased. Murray initially approached Honda for an NA powerplant with 550 bhp (410 kW; 560 PS), 600 mm (23.6 in) block length and a total weight of 250 kg (551 lb), it should be derived from the Formula One powerplant in the then-dominating McLaren/Honda cars.

Chassis and body

The McLaren F1 was the first production road car to use a complete carbon fiber reinforced plastic (CFRP) monocoque chassis structure. Aluminium and magnesium was used for attachment points for the suspension system, inserted directly into the CFRP.

The car features a central driving position - the driver's seat is located in the middle, ahead of the fuel tank and ahead of the engine, with a passenger seat slightly behind and on either side. The doors on the vehicle move up and out when opened, and are thus of the type butterfly doors.

The engine produces high temperatures under full application and thus cause a high temperature variation in the engine bay from no operation to normal and full operation. CFRP becomes mechanically stressed over time from high heat transfer effects and thus the engine bay was decided to not be constructed from CFRP.

Aerodynamics

The overall drag coefficient on the standard McLaren F1 is 0.32, compared with 0.36 for the faster Bugatti Veyron, and 0.357 for the current holder of the fastest car world record (as of 2008) - the SSC Ultimate Aero TT (in terms of top speed). The vehicle's frontal area is 1.79 square meters and the total Cx is 0.57. Due to the fact that the machine features active aerodynamics these are the figures presented in the most streamlined configuration.

The normal McLaren F1 features no wings to produce downforce (compare the LM and GTR editions), however the overall design of the underbody of the McLaren F1 in addition to a rear diffuser exploits ground effect to improve downforce which is increased through the use of two electric fans to further decrease the pressure under the car. A "high downforce mode" can be turned on and off by the driver. At the top of the vehicle there is an air intake to direct high pressure air to the engine with a low pressure exit point at the top of the very rear. Under each door is a small air intake to provide cooling for the oil tank and some of the electronics. The airflow created by the electric fans not only increase downforce, but the airflow that is created is further exploited through design, by being directed through the engine bay to provide additional cooling for the engine and the ECU. At the front, there are ducts assisted by an electric suction fan for cooling of the front brakes.

There is a small rear spoiler on the tail of the vehicle, which is dynamic, the device will adjust dynamically and automatically attempt to balance the center of gravity of the car under braking - which will be shifted forward when the brakes are applied. Upon activation of the spoiler a high pressure zone is obviously created in front of the flap, this high pressure zone is exploited—two air intakes are revealed upon application that will allow the high pressure airflow to enter ducts that route air to aid in cooling the rear brakes. The spoiler increases the overall drag coefficient from 0.32 to 0.39 and is activated at speeds equal to or above 40 mph (64 km/h) by brake line pressure.

0 comments:

Post a Comment