At the start of May every year, the Wörthersee is the place to be for every car and Audi aficionado. Audi will therefore be showcasing a special highlight in 2013: the Audi TT ultra quattro concept. The showcar combines a lean 1,111 kilograms (2,449.34 lb) total weight with a 2.0 TFSI engine, whose 228 kW (310 hp) and 400 Nm effortlessly propel the coupe. 

From a standstill the TT ultra quattro concept takes 4.2 seconds to 100 km/h (62.14 mph). Its power-to-weight ratio of 3.6 kg/hp is on a par with thoroughbred super sports cars. And it is also worthwhile looking at the detail, not least because the concept car pays homage to automotive lightweight construction.

Even the current series-production car with a body weight of just 206 kilograms (454.15 lb) plus 98 kilograms (216.05 lb) for the detachable body parts is testimony to the outstanding lightweight construction expertise of Audi. 

The engineers from Ingolstadt and Neckarsulm concertedly fine-tuned the Audi Space Frame (ASF) in the current TT generation to come up with the body for the Wörthersee showcar, shedding another 43 kilograms (94.80 lb) from the body structure. Together with the optimized detachable body parts, the result is a weight saving of 100 kilograms (220.46 lb).

The Audi TT ultra quattro concept uses carbon-fiber reinforced polymer (CFRP) in the rear end, the center tunnel, in the B-pillars and in the roof. Magnesium components in the floor and as hinge reinforcement reduce weight even further.

The concept car is painted in the special color crystal white. The developers have also fitted the bucket seats from the R8 GT to the concept study; their chassis alone, made out of fiberglass-reinforced plastic (FRP), reduce weight by 22 kilograms (48.50 lb). 

Overall, all these lightweight construction measures make the concept car about 300 kilograms (661.39 lb) lighter than the comparable sporty series-production model. All of which helps minimize the inertial mass that the 228 kW (310 hp) 2.0-liter TFSI engine contends with during acceleration. The modified high-end four-cylinder unit develops its maximum torque of 400 Nm between 1,900 and 5,000 rpm, putting it on a par with the power of the V8. Modifications to the crankcase, the crankshaft, the balancer shafts, the flywheel, the oil sump, the bolts and certain ancillary units that make the engine 25 kilograms (55.12 lb) lighter have all helped get the engine into tip-top shape.

Source: Audi