Porsche unveils Carrera 4 and 4S Coupe and Convertible

Porsche unveils Carrera 4 and 4S Coupe and Convertible
By Ben Whitworth
First official pictures
26 June 2008 11:54
Following on from the driven earlier this month, Porsche has expanded the line-up with the new all-wheel drive Carrera 4 and 4S, both in coupe and convertible form. And like the standard rear-drive Carrera, the 4 and 4S hides it’s new tech under its same-again styling – badging aside, only the 44mm wider rear haunches and that reflective band between the rear lights distinguish the two and four-wheel variants.
So what has changed?
Well, there’s an all-new four-wheel drive system, for starters. Porsche has ditched the previous viscous multiple-plate clutch layout for its new electronically-controlled Porsche Traction Management (PTM) set-up, claiming better stability and enhanced dynamics from the quicker system. Initially developed for the 911 Turbo, the PTM has been modified for the Carrera and now features a mechanical limited slip diff on the rear axle.
Keep going…
Porsche claims the PTM system uses an electronically-controlled multi-plate clutch to metre out the exact amount of torque between front and rear axles. With the previous viscous system, only a maximum of 40% torque could be fed through the front axle – the new system’s infinitely variable torque splitter can shift up to 100% torque between front or rear axles, enhancing cornering stability and boosting all-weather traction.
Anything else?
The four-wheel drive versions share the standard Carrera's new direct injection powerplants, as well as the option of the new seven-speed PDK double-clutch transmission. Delivering more power from less fuel, the 3.6 and 3.8-litre flat sixes in the 4 and 4S return some pretty impressive economy figures: the 345bhp Carrera 4 coupe with PDK transmission gives 28mpg, while the 385bhp 4S cabriolet (again with PDK) returns 26.4mpg on the combined cycle.