|February 3, 2003
Further Details: Audi TT 3.2 quattro With Direct Shift Gearbox (DSG)
Audi is presenting its TT sports car for the first time with a six-cylinder engine and innovative transmission technology. This enables a particularly dynamic transmission of power with an uninterrupted power flow during gear changes. The combination of the high-torque 3.2-litre engine with innovative sports gearbox and quattro permanent four-wheel drive emphasises the dynamic driving qualities of the Audi TT in a unique way. The new TT 3.2 quattro will be offered as both Coupé and Roadster versions.
The 250 bhp version of the Audi TT Coupé 3.2 quattro completes the sprint from 0 to 100 kilometres per hour in 6.4 seconds, whilst its top speed is gently governed at 250 km/h. This model has an overall fuel consumption of 9.8 litres per 100 km. These figures speak for themselves, even when compared with vehicles with a classic 6-speed manual gearbox. The differences compared with the conventional geared automatic transmission with torque converter are even more impressive, since the latter is prone to significantly higher transmission losses due to its fundamental concept.
The source of the power is the proven 3.2-litre V6 engine with four valves per cylinder. The six-cylinder engine is particularly well-suited to the sporty Audi TT by virtue of its outstanding torque and power characteristics, especially in combination with the new twin-clutch transmission. The engine now delivers 184 kW (250 bhp) and a broad peak-torque range with a maximum value of 320 Nm from 2,800 to 3,200 rpm.
With its cylinder angle of 15 degrees, the V6 is extremely compact - a basic requirement for installation transversely to the direction of travel. The valve control process generates only little friction thanks to the use of roller cam followers with hydraulic adjustment. In order to reduce emissions and further improve efficiency, the inlet and exhaust camshafts are continuously adjustable. The compression ratio is 11.3:1.
Other technical details such as the variable intake manifold and the modified intake ports give the six-cylinder engine superior torque and power output, coupled with low emissions. A great deal of detail work has once again been invested particularly in the area of the cylinder head and air intake in order to improve still further on peak output and torque characteristic for use in the TT.
In its new role in the TT, the engine complies with the strict emission standards that apply for the USA and Japan, and of course with the EU4 standard.
Throttle valve actuation is designed for an exceptionally agile, spontaneous engine response to accelerator pedal movements. The way it interacts particularly with the ultra-rapid, precise control technology of the new Direct-Shift Gearbox with twin clutch opens up an entirely new dimension in propulsive power. The close connection between throttle and transmission control is made particularly apparent by active throttle blips during downshifts in the selector lever position S and in the manual gate.
The sound of the dual-branch variable exhaust system suitably reflects these sporting characteristics. A flap in the exhaust system is opened or shut depending on engine speed and the acoustics influenced accordingly. The sonorous sound never becomes over-assertive, even at high engine speeds, yet it unmistakably conjures up all the sentiments that sports-minded TT drivers appreciate.
Transmission technology at Audi
Audi has a long tradition in the development of innovative transmission technologies and their use in production vehicles. The tiptronic, for example, which enables very sporty gear changes and manual intervention at any time, was first introduced on the A8 in 1994.
Since 1999, the innovative continuously variable multitronic transmission has been setting new standards in terms of acceleration comfort and economy. Thanks to its ingenious design and control logic, it is a sporty alternative to the conventional geared automatic transmission.
In the world of automatic transmissions, the Direct-Shift Gearbox is now following the tiptronic and multitronic as a further milestone in transmission technology at Audi.
This transmission principle, however, is not unknown territory for Audi. The technology of the twin-clutch transmission has its roots in motor racing. Audi used it in the legendary Audi Sport quattro back in 1985, with Walter Röhrl behind the wheel. He completed successful test drives in the Audi Sport quattro S1, a rally vehicle whose victories included the legendary Pikes Peak Hill Climb.
The new Direct-Shift Gearbox DSG
The revolutionary Direct-Shift Gearbox combines the advantages of a conventional 6-speed manual gearbox with the qualities of a modern automatic transmission. The driver thus benefits from enormous agility and driving enjoyment with acceleration that is as harmonious as it is dynamic, without any interruption in the power flow. This is combined with good economy thanks to low fuel consumption, and convenient operation.
The basis for this new development is a three-shaft 6-speed manual gearbox which offers considerable variability in the selection of the transmission ratio. Thanks to the use of a twin multi-plate clutch with ingenious electro-hydraulic control, two gears can be engaged at the same time.
During dynamic operation of the car, one gear is engaged. When the next gearshift point is approached, the appropriate gear is preselected, but its clutch kept disengaged. The gearshift process opens the clutch of the activated gear and closes the other clutch at the same time with a certain overlap. The gear change takes place under load, with the result that a permanent flow of power is maintained.
The control logic integrated into the transmission casing maintains optimum gearshift strategies that perform lightning-fast gearshifts that are nevertheless smooth and almost jolt-free. The driver can directly influence the gear selected and the gearshift timing at will, by means of the gear lever in the manual gate or, in the style of a racing driver, using the standard-fit shift paddles on the steering wheel.
In the automatic mode, the driver can shift to the ultra-sporty S program in which upshifts are significantly retarded, downshifts advanced and the shifting process accelerated. A remote one-touch function accessed via the shift paddles on the steering wheel in addition temporarily calls up the manual mode, even in automatic modes D and S.
The design of the transmission gate with a high-quality aluminium surface is reminiscent of typical Audi tiptronic or multitronic counterparts.
High overall efficiency is thus combined with superlative road performance and ease of operation to produce an exceptional drive concept.