One of the impressive technical features for which Audi’s new turbocharged engines are noted is the design of the inlet ports.They impart a "tumble effect" to the charge air as it enters the combustion chamber. This effect increases the speed of the combustion process and thus ensures more complete combustion. The engine’s efficiency is increased and its pollutant emissions are lowered. In this area the TT also benefits from the know-how acquired with the new V6 "biturbo" engine.

The new Audi turbocharged engines feature the latest electronic engine management generation, Motronic ME 7.5.

The sheer number of functions that this adaptive system controls is most impressive: throttle butterfly position, boost pressure control, sequential fuel injection with air mass measurement by means of a hot-film sensor, mapped ignition characteristic with solid-state high-tension distribution system including individual coils for each cylinder, and cylinder-selective knock control with two sensors.

The engine management system senses the amount of torque which the driver wishes to have transmitted to the driven wheels and decides how this wish can be fulfilled most rapidly and economically; it then adjusts the throttle butterfly position, turbocharger boost pressure and ignition timing to the most suitable settings.

This was the approach which also led to just about every running-gear element being redeveloped to the necessary extent. The front axle for the 132 kW front-wheel-drive car and for the two quattro versions is of MacPherson strut pattern, with new forged lower control arms, new guide joints with larger-diameter journals, new cast steel pivot bearings and specially chosen axle geometry. The anti-roll bar is pivoted directly on the spring strut at each side.

For the TT quattro, the choice fell on a rear suspension layout with combined trailing and double lateral control arms. This is a particularly space-saving design with the springs and shock absorbers mounted separately, the latter at an angle.

True-running and equally compact in design, the rear axle for front-wheel-drive cars has torsion-crank suspension. Track, camber and toe geometry has been matched to the car’s sporting character.

Both rear-axle versions include an anti-roll bar. It further increases the resistance to body roll already assured by the firm suspension settings. On the TT quattro the anti-roll bar is pivoted to the wheel hub backplate by means of a connecting linkage at each side, on front-wheel-drive cars a tubular anti-roll bar is welded into the rear axle assembly.

The Audi TT Coupé has disc brakes at front and rear. The front discs are ventilated, on the more powerful version those at the rear as well. Disc diameters of 312 mm at the front and 256 mm at the rear take the car’s high performance into account. The fist-type rear brake calipers are made of aluminium. This saves weight, in particular unsprung mass at the wheels, so that oscillation is reduced and dynamic stability improved. Heat dissipation is also better when the brakes are subject to severe loads.

The very latest electronic "co-pilots" ensure optimum traction, dynamic stability and safety in varying conditions. All TTs have anti-lock braking (ABS) as standard, and also an electronic differential lock (EDL) in the front axle and electronic braking-pressure distribution (EBD). In addition, the 132 kW front-wheel-drive version has Traction Control (ASR).