AUDI has lifted the lid on the car the German company describes as its most exhilarating RS convertible to date - the new 450PS RS 5 Cabriolet.

Order books for the elegant rag-top open later this year ahead of a springtime arrival, but first the new Audi will make its debut at this month's Paris Motor Show.

Beneath the bonnet is the same 4.2-litre V8 engine shared with the RS 4 Avant while above is a fast-acting lightweight fabric roof.

At the push of a button it opens and closes automatically in 15 and 17 seconds - when driving at up to 31mph - and when open, it barely affects the size of the luggage compartment, only requiring 60 litres of its 380-litre volume.

As in the Coupe, the V8 petrol engine is hand built for the RS 5 and can rocket the cabrio from 0-62mph in 4.9 seconds and on to a Governed 155mph, though the top speed can be elevated to 174mph at extra cost.

Transmission is via Audi's familiar seven-speed S tronic dual-clutch transmission and permanent quattro all-wheel-drive is backed up by torque vectoring.

But even with technologies like a recuperation system, the car is still only capable of a Combined 25.9 miles per gallon.

The RS actually sits 20 mm lower than the Audi A5 Cabriolet, its mounts are stiffer and it has larger, firmer anti-roll bars.

Carbon fibre ceramic brake discs are available at extra cost as is the Dynamic Ride Control stability system, a dynamic steering option and a sports exhaust system with black tailpipes.

In the multimedia field, the RS 5 Cabrio gets Mobile Phone Preparation - High with Audi connect option, which lets passengers surf the web with mobile devices via an integrated WLAN hotspot.

Prices have yet to be confirmed but are expected to be around the £70,000 mark.