With their composite construction concept, the bodies of both RS models represent a new evolutionary stage of the Audi Space Frame (ASF). The front end and the floor of the passenger compartment includes many hot-stamped steel components, which thanks to their extreme rigidity only require low wall thicknesses and are therefore very light. The structure of the passenger compartment, the outer skin and all add-on parts are made of aluminum in the classic semi-finished products cast nodes, extruded profile and sheet metal.
The new TT RS Coupé has a curb weight (excluding driver) of just 1,440 kg (3,174 lb) – 35 kg (77.2 lb) less than the already very light previous model. Each one of its 400 hp only has to move 3.6 kg (7.9 lb). The new TT RS Roadster has a curb weight of 1,530 kilograms (3,373.1 lb) and thus has a power-to-weight ratio of 3.8 kilograms (8.4 lb). Its body has been additionally reinforced compared with the Coupé. The aluminum A-pillars enclose a second pillar of steel, which in turn encloses an additional steel tube. Internal steel ribbing provides for the high strength of the aluminum sills. Diagonal struts designed specifically for the RS reinforce the rear end. A wall made of two steel box profiles separates the passenger compartment from the luggage compartment. This replaces the floor cross-member of the Coupé. The steel roll-over bars are integrated into the upper section of the wall.
Opens or closes in ten seconds: the cloth top
The convertible top of the TT RS Roadster is an automatic acoustic soft top made of cloth. With its substructure components of magnesium, aluminum, steel and polymer, it weighs just 39 kilograms (86.0 lb), three kilograms (6.6 lb) less than in the previous model.
The soft top sits low and flows smoothly over the body. The side windows are short. While opening, the top forms a Z shape as it folds together into a flat package. It is stored in an aluminum compartment that does not reduce the available volume of the luggage compartment. The electric drive opens or closes the soft top in just 10 seconds, even while driving at speeds up to 50 km/h (31.1 mph). Graphics in the Audi virtual cockpit illustrate the process as it is happening. If the convertible top loses tension, the two electric motors pull it tight again.
The thermal and acoustic insulation of the TT RS Roadster is outstanding. The fleece layer above the headlining plays an important role here. The five-layer structure has a total thickness of 15 millimeters (0.6 in) (plus headlining). The levels of road and wind noise picked up inside the car are thus much lower than in the previous model. Audi provides a power-extending wind deflector as standard. Headroom heating for the RS sport seats is available as an option.
The equipment, data and prices specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.