In the Audi TTS, the 2.0 TFSI delivers 380 Nm (280.3 lb-ft) of torque between 1,800 and 5,700 rpm. Numerous details underscore its high-performance character. Modified aluminum pistons and higher-strength connecting rods with new bearings transmit the forces to the crankshaft. The crankcase has been reinforced at the main bearing seats and the main bearing cover.
The cylinder head is made of a lightweight aluminum-silica alloy with high strength and temperature resistance. The valve springs and seat rings have been modified for the high loads.
With a maximum charge pressure of 1.2 bar, the large turbocharger can compress up to 1,000 kilograms (2,204.6 lb) of air per hour. A high-performance air-to-air intercooler reduces its temperature dramatically.
Equipped with the six-speed S tronic, the new Audi TTS springs from zero to highway speed in 4.6 seconds en route to an electronically governed top speed of 250 km/h (155.3 mph). In the NEDC, the top model with the S tronic consumes on average just 6.8 liters of fuel per 100 kilometers (34.6 US mpg), corresponding to 157 grams CO2 per kilometer (252.7 g/mi).
The powerful 2.0 TFSI is a pure sports engine. It reacts spontaneously to the throttle and revs up to the redline of 6,800 rpm. In automatic mode of the Audi drive select system, it responds even more directly with brief double-clutching underscoring the change of gears by the optional S tronic. At higher loads and rpm, two sound flaps in the exhaust system open to provide an even fuller sound.
Transmissions
The new Audi TT and TTS come standard with a manual six-speed transmission with a lightweight magnesium housing. It features short throws for easy and precise gear changes. The two TFSI engines are optionally available with the six-speed S tronic, which is likewise very efficient. As with the manual transmission, its internal gearing features sportily short ratios. The tall top gear helps reduce fuel consumption.
Six-speed S tronic
The six-speed S tronic makes the new TT and TTS even more dynamic. It changes gears within a few hundredths of a second and with no noticeable interruption of power. Gear changes are very comfortable. The driver can choose between automatic or manual mode, in which it can be controlled using either the selector lever or paddles on the steering wheel. In automatic, D mode is designed for low fuel consumption and long ratios. In S mode, the driving style is sporty and the revs are higher.
Another special feature of the six-speed S tronic is fuel-saving freewheeling function. It is activated when the Audi drive select system (optional in the TT, standard in the TTS) is set to efficiency mode and the driver lets off the accelerator. The Launch Control start program in the TTS and the TT 2.0 TFSI with S tronic manages full acceleration from a standstill with controlled wheel slip.
Like all dual-clutch transmissions, the new six-speed S tronic comprises two independent transmission structures. Two radially arranged multi-plate clutches actuate the gears. The large K1 clutch directs the engine torque via a solid shaft to the gear wheels for the odd-numbered gears 1, 3 and 5. A hollow shaft rotates around the solid shaft. It is connected to a second, smaller K2 clutch, which is located inside its larger sibling and acts on the gear wheels for gears 2, 4, 6, and reverse.
Both transmission structures are continuously active, but only one of them is connected to the engine at any one time. Shifts are performed by switching the clutches. When the TT is accelerating in third gear, for instance, fourth gear is already selected and the K2 clutch is disengaged. As soon as the command to shift gears is given, K1 disengages while K2 engages. Every transmission speed is assigned a conventional switching unit, as a result of which it is also possible to change directly from sixth to fourth gear, for instance.