Porsche has continued its tradition of only implementing minimal changes to the styling of its iconic 911 range for the latest 2009 model year facelift, but the changes taking place under the new sheet metal are quite the opposite. This is because the new 911 Carrera is available for the first time with direct injection and dual clutch technologies.
The first cars to receive the updates are the Carrera and Carrera S models, both of which are now available with Porsche’s newly developed Doppel Kupplung (dual clutch) gearbox complete with seven forward gears.
For the 2009 model year, the Carrera and Carrera S will get a new optional seven-speed automatic double-clutch gearbox dubbed Porsche-Doppelkupplung (PDK) along with a new direct injection system– the first time we have seen this in a Porsche sportscar. The new double-clutch gearbox replaces the Tiptronic S automatic transmission and now allows the gear changes without any break or interruption to traction and pulling power.
Porsche has already applied direct injection technology to the 4.8L V8 Cayenne SUV but implementing the technology in the flat-six of the Carrera models has been a more daunting task - although the payoff of greater power, torque, fuel-efficiency and emissions ratings was an enticing incentive for Porsche.
Engineers have increased the size of the combustion chambers, upgraded the crankshaft and installed new oil and water pumps in order to implement the direct injection technology, raising the redline to 7,500 rpm, 200rpm higher than the non-direct-injection flat-six.
The 3.8L flat-six gets a significant improvement in horsepower thanks to the technology, with power rising from 350hp to 380hp and torque climbing from 295lb-ft at 4,600rpm to 310lb-ft at 4,400 rpm. According to Porsche, the updated Carrera S with direct injection and the new seven-speed dual clutch transmission should hit the 60mph mark in 4.3 seconds, an improvement of around four-tenths of a second over the current model.
While more horsepower is always welcome, consumers these days want to see fuel efficiency improve and Porsche doesn’t disappoint in this area either. The 3.8L 911 Carrera S with dual-clutch transmission consumes up to 12.8% less fuel and emits around 14.5% less carbon-dioxide than its predecessor, while the 3.6L 911 Carrera experiences similar gains. The combination of greater efficiency due to direct injection and minimal loss of power thanks to the dual clutch transmission allow the two sports cars to achieve these significant gains.
A new butterfly valve has also been adopted in the 3.8L, opening at around 5,100rpm to really allow the Porsche’s bark to match its bite, although the 3.6L in the base Carrera doesn’t get this treatment.
Changes to the 911’s exterior consist of new LED taillights, slightly revised bumpers with daytime running lights and new 18 and 19in wheels. The rest of the 911 fleet, including the Carrera 4S and Turbo, are expected to adopt the same changes in the coming year.
Source: allworldcars.com
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