Porsche has revealed details for the new all-wheel-drive versions of its 911 coupe and convertible for 2009.

Both the Carera and the Carrera4S are to receive tweaks to increase the cars’ performance, improve their fuel economy and cut their emissions.

With direct-injection fitted to the 3.6-litre and 3.8-litre six cylinder engines, the Carrera 4 is to get an extra 20 horsepower, bringing it to 345hp, while the 4S will get a 30 horsepower boost up to 385hp.

The old multiple-plate clutch system is to be replaced with an electronically controlled Porsche Traction Management system which was originally developed for the Porsche 911 Turbo.

Porsche’s double-clutch system will be available as an alternative to the existing six-speed manual transmission.

The new 911 also has more cosmetic changes. Starting next year models will come with light-emitting diode (LED) daytime driving lights.

And, for the first time Porsche is to offer lights which move in the direction of the steering wheel.

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