|3rd generation Audi TT. Click to enlarge.|
Audi is unveiling the third-generation of its TT compact sports car at the Geneva Motor Show. (The first generation arrived on the market in 1998.) The new TT and TTS models will be available with three different four-cylinder engines with turbocharging and direct injection. A start-stop system is a standard feature.
For the launch of the TT, the 2.0 TDI diesel will be available with manual shift and front-wheel drive. It delivers 135 kW (184 hp) and torque of 380 N·m (280 lb-ft). The new sports car can accelerate from 0 to 100 km/h (62 mph) in 7.2 seconds and reaches a top speed of 235 km/h (146 mph). Standard fuel consumption is 4.2 liters per 100 km (56 mpg US), which translates into CO2 emissions of 110 g/km (177 g/mile).
The 2.0 TDI features two balancer shafts in the crankcase, adjustable camshafts and a common rail injection system delivering maximum pressure of 2,000 bar. The Audi TT 2.0 TDI meets the Euro 6 standard.
The 2.0 TFSI is available in two versions: a 169 kW (230 hp) version for the TT and a 228 kW (310 hp) version for the TTS. In both versions it unites various advanced technologies: additional indirect injection supplementing the direct injection of the FSI; the Audi valvelift system (AVS) to adjust the valve stroke on the exhaust side; and thermal management, which uses a rotary valve module and an exhaust manifold integrated into the cylinder head.
In the Audi TT, the 2.0 TFSI delivers torque of 370 N·m (273 lb-ft) from 1,600 to 4,300 rpm. It accelerates the Coupé—which has a six-speed manual transmission and front-wheel drive—from 0 to 100 km/h in 6.0 seconds, and on up to an electronically governed top speed of 250 km/h (155 mph).
On the version with six-speed S tronic and quattro all-wheel drive, accelerating from 0 to 100 km/h takes 5.3 seconds; top speed is 250 km/h (155 mph); fuel consumption of 6.8 liters per 100 km (35 mpg US ) and CO2 emissions of 159 g per km (256 g/mile).
In manual model, the six-speed dual-clutch transmission can be controlled by paddles on the steering wheel. In the “efficiency” mode of Audi drive select, the S tronic selects freewheel as soon as the driver takes his or her foot off the gas pedal.
The Audi TTS is the peak performer. It covers the standard sprint in 4.7 seconds; its top speed is electronically governed at 250 km/h (155 mph). The 2.0 TFSI produces 380 nm (280lb-ft) of torque at an engine speed of between 1,800 and 5,700 rpm. Controllable flaps in the exhaust system modulate the sporty sound and make it even richer. A manual transmission is standard. The S tronic option includes launch control, which regulates maximum acceleration from a standstill.
quattro drive. quattro permanent all-wheel drive has been consistently advanced and optimized especially for the new TT. Its electro-hydraulically controlled multi-plate clutch is mounted on the rear axle. The special pump design reduces weight by around 1.5 kg (3.31 lb) compared with the previous model. The distribution of drive torque between the axles is controlled electronically within fractions of a second.
Software that determines precisely the possible torque distribution between the front and rear axles is a completely new development especially for the TT. The innovative control philosophy continuously senses the ambient conditions, driving status and the driver’s wishes. Optimized distribution of torque is calculated and the TT’s dynamic drive characteristics enhanced in every situation.
By networking quattro drive with Audi drive select, the driver of the new Audi TT can adjust the all-wheel-drive properties to suit his or her individual requirements.
In “auto” mode, this produces optimum traction and balanced driving dynamics. In “dynamic” mode, torque is distributed to the rear axle earlier and to a higher degree, which means that driving dynamics are enhanced further, especially on surfaces with low friction coefficients.
Alongside optimizing the driving dynamics, the advances made to quattro drive also focused on the subject of efficiency. In the drive select “efficiency” mode the torque distribution is adjusted to optimize the level of efficiency. Determining driving conditions and driver type precisely allows for efficiency-optimized all-wheel-drive control—which can even result in the temporary shutdown of the quattro drive system. In this operating state, the intelligent software carefully monitors the driving situation and activates the all-wheel drive before torque is once again required at all four wheels. In this way, quattro drive provides optimum efficiency along with a level of traction and dynamic handling that is typically quattro.
Body. The second-generation Audi TT featured an Audi Space Frame (ASF) body made from aluminum and steel. For the new TT, Audi has systematically taken this composite construction principle even further. The Coupé’s underbody structure has optimized axle loads and is made of high-strength and ultra-high-strength steel alloys.
In the sections of the passenger cell that are subject to the most structural stress, form-hardened steel panels, which are both ultra-high-strength and light are used; these constitute 17 percent of the body’s weight. The side sills and roof frame are made of extruded aluminum profiles that are integrated into the structure using cast aluminum nodes. This structural principle creates a very rigid and safe bodyshell. The aluminum side sections and roof complete the structure. The hood, doors and trunk lid are also made of this light metal.
All in all, the Audi engineers have, for the second time in a row, succeeded in significantly reducing the unladen weight of the Audi TT. At the first model change in 2006, up to 90 kg (198 lbs) were saved. The 2.0 TFSI engine variant of the new TT weighs just 1,230 kg (2,712 lbs). This makes it around 50 kg (110 lb) lighter than its predecessor.
The low overall weight positively impacts especially on acceleration, handling and fuel consumption.
Chassis. The front suspension is based on a McPherson system; aluminum components reduce the weight of the unsprung chassis masses. The four-link rear suspension can process the longitudinal and transverse forces separately.
One particular highlight is the new third generation of the adaptive damper control system, Audi magnetic ride. Compared with the previous version, it has been improved in terms of characteristic spread, control dynamics and precision as well as user friendliness. Audi magnetic ride can be adjusted to three settings (comfort – auto – dynamic) via Audi drive select and, at the press of a button, either makes the compact sports car hug the road more tightly or lets it glide smoothly across the road irrespective of which mode the driver selects.
Magnetic ride technology delivers swift wheel-selective control of the damper forces, which means that in all driving situations there is optimum contact between wheel and road.
Audi magnetic ride is standard on the Audi TTS and is available as an option for all other TT versions.
Another highlight is the standard progressive steering—its rack is designed such that the ratio becomes more direct as the steering is turned. In this way, the new TT can be steered agilely and precisely with little movement of the steering wheel in downtown traffic and on winding country roads. The electromechanically driven progressive steering adapts its assistance to speed and forms the basis for the optional assistance systems: Audi active lane assist and park assist.