PORSCHE Cars Australia expects as many as half of all 911 buyers in this country will in future opt for the latest Cabriolet version whereas last year the percentage was only 30 per cent.

The new 991-series Carrera Cabriolet – which has been in Australian showrooms since last month but was formally introduced to the media this week – is priced from $255,100 plus on-road costs, which is $25,200 more than the equivalent 911 coupe, but arrives with advancements that make it more desirable than ever.

A new soft-top roof design eliminates the visible ribs associated with vinyl-top roofs and provides not just a close resemblance to the coupe’s profile, but is “identical to the millimetre”, according to PCA public relations manager Paul Ellis.

“We think the take-up rate for the Cabriolet will change because it is quite stunning visually,” he said.

“It is the same as the Coupe to the millimetre and we think that will encourage some people to look at the Cabriolet over the Coupe.”

Mr Ellis said that Cabriolet sales accounted for around 30 per cent of 911 volume last year – about 60 out of 201 – and he would “not be surprised if it nudged 50 per cent” with the new model.

The Cabriolet model line-up echoes that of the Coupe, so in addition to the base 3.4-litre Carrera there is a 3.8-litre Carrera S model that costs $33,200 more at $288,300, fitted with the new seven-speed manual gearbox that made its debut in the 911 Coupe here three months ago.

However, the optional PDK (dual-clutch) seven-speed automatic – which will account for almost all 911 Cabriolet sales – adds a further $5950.

Although the new Cabriolet models are about $10,000 more expensive than the superseded model, Porsche believes the new model is a considerable step forward, being only the third all-new 911 in the 50-year history of the classic sportscar.

Like the Coupe, the convertible is notably larger than its predecessor – the wheelbase alone is some 100mm longer – and carries more equipment, but the search for ever-lower fuel consumption has seen overall weights reduced by between 45kg and 60kg, thanks mainly to the use of numerous aluminium body panels and some magnesium components.

While the Cabriolet still weighs 80kg more than the hardtop due mainly to extra body reinforcement, it benefits from the use of more magnesium and aluminium in the convertible roof frame and folding mechanism.

Longer than before, the roof consists of four large but hidden magnesium panels over the top that provide the coupe-like profile, but it is not a folding hardtop, retaining a full and thicker acoustic ‘fabric’ covering – which is a composite material that includes tough mylar.

PCA technical manager Paul Watson said there was not enough room in the back of the rear-engined 911 for a folding hardtop.

By retaining Porsche’s proven compact Z-fold roof mechanism, the lightweight roof not only folds away in just 13 seconds (at speeds up to 50km/h) but stores neatly right above the rear axle-line in order to have as little effect on the handling as possible.

Also located near the rear axle is a more compact rollover protection system that activates to protect the occupants’ heads.

One of the four roof panels houses the rear window, which is a normal glass unit and impressively fits almost flush with the fabric skin.

Another improvement with the 991 series is the standard fitment of an electric-powered wind deflector that lifts automatically to reduce interior buffeting, replacing the previous manual unit that had to be placed in position and stored when not in use.

As with the Coupe, the base Carrera Cabriolet is now powered by a 3.4-litre flat-six engine instead of the previous 3.6-litre unit, but without any loss in performance as it has the same torque output and 3kW more power while being more fuel efficient.

It also contributes 10kg of the new model’s weight reduction.

Another interesting technical development is the automatic rear spoiler, which extends to different heights and angles according to the speed and whether the roof is open or closed.