PARIS MOTOR SHOW: Audi TT Roadster

The convertible Roadster version of Audi's lauded, third-generation TT coupe will arrive with a folding cloth roof and the same sensational cockpit design as its hard-topped brother.

Launched in both TT and TTS forms, the Roadster has matured and had its proportions tweaked compared to the second generation, with a 37mm increase in wheelbase lending a more comfortable cabin, yet the car is 21mm shorter than its predecessor.

It's also 10mm narrower, at 1832mm and is a fraction lower, at 1355mm and it has far shorter overhangs at the ends of its 4177mm body than the second-generation TT Roadster.

It will run the same powertrains as the Coupe, with the TTS's 2.0-litre TFSI turbo motor pumping out 228kW of power and 380Nm to spurt the Roadster to 100km/h in 4.9 seconds. There will also be a lesser version of the engine for stock TT work, with 169kW and 370Nm.

A diesel will also lead the way for Europe, with a 135kW/380Nm output rate and sipping just 4.3 litres/100km.

All engines will be standard with six-speed manual gearboxes, though there will also be a six-speed dual-clutch unit as an option. All-wheel drive is standard on the TTS Roadster, but optional on the 2.0-litre TFSI and not available on the TDI.

Its styling is heavily drawn from the Coupe, with a large, single-element grille, optional LED headlights and Matrix LED headlights along with chiseled body creases.

Three kilograms lighter than the roof on its predecessor, the Z-shaped fold drops in just 10 seconds down into an alloy tray in the boot, leaving 280 litres of luggage capacity whether it's up or down. It can be lowered or raised while driving at speeds of up to 50km/h.

Audi says it has focused on reducing cabin noise, insisting it has lowered the interior noise levels by 6dBa when the roof is up at cruising speeds.

The soft-top roof closes to give it a 0.30 coefficient of drag, even with the rear spoiler popping proud of the bodywork above 120km/h. The five-layer fabric top fits over a frame that mixes steel, plastic, aluminium and magnesium to weigh just 39kg, which alone gives a strong hint as to why Audi refuses to follow trends towards folding metal roofs for its TT.

The TT Roadster tips in at just 1320kg in its dry weight, thanks partly to its Modular Transverse Architecture, borrowed from the rest of the Volkswagen Group. That's just 90kg heavier than the Coupe version.

The Roadster has a significantly reinforced underbody to improve the car's torsional rigidity in an effort to replicate the Coupe's chassis dynamics.

Steel pillars stuffed with solid steel tubes have been inserted inside the aluminium A-pillars of the TT to give it more stiffness, while the aluminium sills of the Coupe have had steel ribs inserted into them. There are also struts in the engine bay and the boot. Architecturally, the biggest change is that the Coupe’s rear bottom cross member has been replaced by two stronger box profiles, one of which plays host to the rollover hoops protecting the heads of the occupants.

Like the Coupe, the Roadster version of the TTS has the magnetic ride dampers as standard, while it’s optional on the rest of the range. The TTS Roadster also has the advantage in the wheel and tyre package, with its 225/50 R18 rubber outmatching the 225/50 R17s on the entry-level versions, though Audi will fit it with up to 20-inch wheels and tyres.

It's the same stunning story inside the Roadster as in the Coupe, with its single wing dashboard, bare-bones layout and fully digital instrument cluster containing everything from the navigation to the audio system and the speedo. Audi calls it a 'virtual cockpit'.

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