Tuesday, January 25, 2011

Porsche Boxster, 2009

Porsche Boxster, 2009


 

In 1948, the 356 was the first sports car to bear the Porsche name, and in July that year the lightweight mid-engined roadster achieved its first motorsport victory. In 1953, the Porsche 550 Spyder was launched. This agile, lightweight race car was powered by a high performance 'boxer' engine which took it to countless international victories.

Porsche presented the second generation of the mid-engined Porsche Boxster roadster at the 2008 Los Angeles Motor Show. The highlight of the new generation is the new flat-six 'boxer' engines, developed with new technical features from the ground up, providing not only more power, but also significantly greater fuel efficiency.

A further improvement of both fuel economy and performance is guaranteed by the Porsche Doppelkupplungsgetriebe (PDK), the new double-clutch gearbox now available as an option on both the Porsche Boxster and Boxster S.

Displacing 2.9-litres, the engine of the Porsche Boxster develops 255 bhp (188 kW) in the Boxster, an increase of 10 horsepower over the prior 2.7-litre model.

The 3.4-litre power unit in the Porsche Boxster S now features Direct Fuel Injection, and delivers 310 bhp (228 kW), up by 15 bhp.

Direct Fuel Injection standard on 3.4-litre S engine
The driver benefits from a further advantage of direct injection every time they touch the throttle pedal: with fuel being injected fractions of a second prior to combustion, the engines respond more directly and spontaneously to even the slightest movement of the driver's right foot. This is not only the case when accelerating, but also when lifting off the throttle, for engine speed drops more quickly and smoothly since there is no residual fuel left in the intake manifold which might otherwise prolong the combustion process.

Design emphasises performance
The seamless blend of function and design has always been the Porsche philosophy. The result is a design consistency which is recognisable from every angle. A design which is both powerful and refined, and whose lines emphasise its sports performance.

The evolutionary styling of the next generation Porsche Boxster embodies these principles. The latest models are clearly distinguishable from outside through their newly-designed nose and tail. The new halogen headlights with their integrated direction indicators are reminiscent of the lights on the Carrera GT, while at the rear, new LED lights taper to the outside and are integrated elegantly in to the restyled bodywork.

PDK: shifting gears more quickly, reducing fuel consumption
The new Porsche Boxster models are available with the Porsche-Doppelkupplungsgetriebe (PDK) carried over directly from motor sport, and replacing the former Tiptronic S torque converter automatic transmission. When equipped with PDK, the Porsche Boxster accelerates from 0-62mph (100 km/h) 0.1 seconds faster than with the manual six-speed gearbox.

Acceleration is particularly fast and dynamic with the optional Sports Chrono Package Plus featuring Launch Control; this offers maximum acceleration from a standing start and also a Race Track Gearshift Strategy for the fastest conceivable gear change as an exclusive highlight on the PDK models.

Porsche Doppelkupplungsgetriebe (PDK) - in detail
The next generation Porsche Boxster and Boxster S are available for the first time with the new Porsche Doppelkupplungsgetriebe (PDK), literally Porsche double-clutch gearbox. Offering no less than seven forward gears, the new gearbox combines the driving comfort of a torque converter-equipped automatic transmission with the dynamic manual gearshift functionality of a sequential racing gearbox. PDK also boasts an entirely automatic gearshift function, and replaces the Porsche Tiptronic S automatic transmission previously offered. Through its optimised and adaptive gearshift programmes, PDK further improves the acceleration of the Porsche Boxster models and reduces fuel consumption to an even lower level.

In principle, the PDK consists of a conventional manual gearbox and a hydraulic control system divided into two separate transmission units. Two wet clutches in radial arrangement, controlled hydraulically, and using oil for both cooling and lubrication, form the heart of the transmission. One clutch is for the first transmission unit with the uneven gear ratios (1,3,5,7) and reverse, and the other clutch is for the second transmission unit with the even gears (2,4,6). Via a number of pressure valves, the hydraulic control unit masterminds both the wet clutches and the shift cylinders activating the transmission ratio required.

The gearshift perceived by the driver comes not from the gears actually changing, but from the change of positive clutch engagement. In this case, the clutch on one transmission opens or disengages while the clutch on the other transmission closes or engages in a simultaneous process. The big advantage is an even faster gearshift than with a conventional manual gearbox or torque converter automatic transmission. The gears are already 'in mesh' when shifting and the power of the engine need not be interrupted in the process.

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