All-new for 2005, the Porsche 911 Carrera and Carrera S receive only subtle changes on the outside – most notably new round headlights – but major upgrades to the mechanicals and cabin.

For the first time since 1977, the 911 comes with two engines: a 325 hp 3.6-litre horizontally-opposed six-cylinder in the Carrera, and a 355 hp 3.8-litre horizontally-opposed six cylinder in the S.

Along with its larger engine, the S also receives the new Porsche Active Suspension Management technology, larger brakes with red-painted calipers, larger wheels, bi-xenon headlights, sports steering wheel, aluminum-look interior trim and a silver-coloured rear deck lid logo as standard equipment.

Changes for 2005 to both models include a new six-speed manual transmission, variable-ratio rack-and-pinion steering, a Sport Chrono Package Plus that records and displays lap times, new seating options, and curtain airbags.

The new models have a 21 mm wider front track and 34 mm wider rear track over the 2004, although the wheelbase remains the same. The suspension has been widened as well, by 30 mm in front and 34 mm in rear. New hollow front pivot axle bearings replace previously solid components to reduce weight and improve airflow to the brakes, while hydraulic suspension mounts minimize vibration to the steering system. Rear suspension mounts with internal elastic foam reduce weight by 45 per cent and improve noise and vibration control.

Porsche’s new Active Suspension Management (PASM) uses active damping to change the suspension from Normal to Sport at the touch of a button. The system incorporates five special software modules to respond to rapid steering wheel movements to reduce swaying, vertical movement on a bumpy road, variable damping through curves, brake actuation to reduce body dive, and load change under rapid acceleration.

The Carrera uses the first standard 18-inch wheels in its history, while the S rides on 19-inch wheels. Brake cooling has been improved and servo power has been increased 17 per cent to reduce pedal force and enhance braking response. Ceramic composite brakes, previously available only on special models such as the 911 Turbo, are available for the first time on the Carrera and Carrera S.

On the inside, both models receive new steering wheels with multifunction controls, new lighter and stronger seats, new gauge cluster, improved climate control, standard Porsche Communication Management with available DVD navigation system, updated audio and anti-theft system, and six standard airbags.

The 911 is built in Zuffenhausen, Germany.

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