FRANKFURT MOTOR SHOW: Rolls-Royce Dawn revealed

Rolls-Royce has revealed a drop-top version of its Wraith coupe ahead of its official unveil at the Frankfurt motor show next week.

Called the Dawn, the big new drop-top luxury car is said to be 80 per cent new compared to the Wraith it’s based on, with only the coupe’s rear-hinged doors and grille carried over.

Created to seat four, the Dawn measures in a colossal 5285mm long, 1947mm wide, 1502mm high and has a wheelbase of 3112mm -- making it about the same size as the big Rolls-Royce coupe -- but it weighs in 200kg more at a mammoth 2560kg.

The new Dawn resurrects its name and design inspiration from the Silver Dawn convertible that was made between 1950 and 1954 but does something the old timer could never dream of -- retract its huge electric roof in just 21 seconds at speeds of up to 50km/h.

Roof up, the British luxury car-maker claims it is as quiet as the regular Wraith and also matches the fixed-head coupe’s ‘magic carpet’ ride quality.

Despite hacking off the roof, Rolls-Royce also claims that the Dawn is the most rigid-bodied four-seat convertible on the market.

To ensure the Dawn is as good to drive as the Wraith, engineers have rethought the coupe’s air suspension. They’ve also widened the rear track by 24mm and added a stiffer anti-roll bar to boost stability .

Powered by the same 6.6-litre twin-turbo V12 that propels the 420kW/780Nm Wraith, the Dawn can sprint from rest to 100km/h in 4.9 seconds before topping out at a limited 250km/h.

At the pumps, the Dawn is claimed to average 14.2L/100km while CO2 emissions are 330g/km.

When the Dawn joins the Rolls-Royce range in the first quarter of next year, it will be the sixth car the British car-maker currently manufactures at its Crewe HQ.

When it reaches Australia some time towards the end of 2016 the new Dawn is expected to cost $650,000.