WE ALREADY know there is plenty to love about the rear-drive Porsche 911 Carrera – its unburstable power delivery and Velcro-like grip, to name just a few.

Now the German sportscar has made the buying process just a tad more interesting by adding the all-wheel drive Carrera 4 and Carrera 4S variants to the line-up at a $15,000 premium over the rear-drive models in Australia.

This brings to eight the number of 997-series 911 models available in Australia, starting at $195,225 for the Carrera coupe and ending, for the moment, at $263,800 for the Carrera 4S cabriolet auto.

Porsche has confirmed that the next-generation GT3 and Turbo models will join the fray around June next year.

Like its rear-drive siblings, two engine sizes are available in the all-paw models, the 3.6-litre Carrera 4 and 3.8-litre Carrera 4S, both mated to either a six-speed manual gearbox or five-speed Tiptronic auto.

The 3.6-litre delivers 239kW at 6800rpm and 370Nm at 4250rpm while the 3.8-litre ups the ante to 261kW at 6600rpm and 400Nm at 4600rpm.

On the road, the Carrera 4 hits 100km/h in 5.1 seconds and has a top speed of 280km/h while the S is 8km/h faster and accelerates to 100km/h in 4.8 seconds.

Visually, both all-wheel drive cars echo the remainder of the range, except for the small "4" on the rear deck and the extra 44mm in body width over the rear wheels.

The extra width flares out over each rear wheel by 22mm, accommodating 295/35 ZR18 tyres and 305/30 ZR19s on the 4S.

The 2350mm wheelbase is unchanged, and the suspension configuration remains McPherson struts up front and a sophisticated independent multi-link arrangement at the rear.

Fuel tank capacity has grown five litres to 67 litres and the luggage area has been redesigned, lifting capacity to 105 litres, or enough space for two suitcases.

The previous space-saver spare wheel has been ditched in favour of a tyre repair system that consists of a tyre pressure compressor and tyre sealant.

Despite the addition of four-wheel drive and the wider rear-end, both the coupe and convertible C4 and C4S have gained just 55kg over the two-wheel drive versions, mostly over the front axle to accommodate the four-wheel drive system.

The system itself uses a viscous multiple-plate coupling to deliver a minimum of five per cent power to the front wheels, increasing to a maximum of 40 per cent when required.

The cabrio gains 85kg mostly to reinforce the windscreen roof structure and for extra body stiffness.

Porsche Stability Management is standard on all models, but four-wheel drive models add two new functions to optimise brake behaviour: a "pre-filling" of the brake system, which moves the pads closer to the discs before hard braking applications, and a brake assist-type system.

Similarly, for the first time the all-wheel-drive Carrera cabriolets are available with the new Porsche active suspension management system, which is optional on the Carrera 4 and standard on the Carrera 4S.

Both the coupe and cabriolet have six airbags fitted standard while the cabrio has an anti-rollover system consisting of super-high-strength steel tubes in the front and two automatically extending rollbars behind the rear seats.

The convertible soft-top opens and closes in 20 seconds at speeds of up to 50km/h. The mechanism weighs 42kg, barely half as much as a comparable "vario" folding roof.

Other standard items onboard include leather upholstery, climate-control air-conditioning, alcantara roof lining (coupe), a nine-speaker Bose CD stereo (with MP3 compatibility), navigation system, sunroof (coupe), bi-Xenon headlights (C4S), aluminium trim highlights (C4S), and height- and reach-adjustable steering.

The "sports chrono package plus", suitably located on the top of the dashboard, is a $2190 option while composite ceramic brakes are a whopping $18,990.

Porsche Cars Australia expects about 20 per cent of all 911 sales to be C4 coupe or cabriolets and it expects to sell around 400 911s next year.