Technical highlights of RS models
The quattro driveline
The RS models with longitudinally mounted engines use the Audi quattro driveline with the mechanical center differential, shown here combined with the sport differential on the rear axle. quattro drive stands for superior stability, traction and dynamics. On exiting corners, the RS models can accelerate earlier with their four driven wheels than is possible in a rearwheel drive car.
The crown-wheel center differential
The compact and lightweight crown gear center differential gets its name from the two special toothed wheels in its interior. During normal operation, it sends the power to the front and rear axles in a ratio of 40:60. It can send up to 85 percent of the torque to the rear and a maximum of 70 percent to the front, if necessary. The distribution of power is broad, fast and homogenous. Torque vectoring is a software solution that complements the work of the crown gear center differential during fast cornering with minimal braking impulses at the inside wheels. The result is sporty, virtually neutral handling with outstanding traction.
The wave brake discs
Many RS models use vented and perforated brake discs in wave design. All together, their wave-like outer contour reduces weight by nearly three kilograms (6.61 lb). Stainless steel pins connect the steel friction rings to the aluminum brake caps. This concept borrowed from racing reduces tensions and quickly dissipates the heat. The calipers on the front axle have either six or eight pistons. quattro GmbH also offers optional carbon fiber-ceramic discs for the front or all four wheels.
The sport suspension with Dynamic Ride Control (DRC)
Audi offers the sport suspension with Dynamic Ride Control (DRC) in the RS 4 Avant and above. It uses steel springs and three-stage adjustable shock absorbers that are connected to one another via diagonal oil lines and a central valve. During fast cornering, the valves regulate the oil flow in the shock absorber of the deflected front outside wheel. They strengthen support and reduce body roll, thus improving even further the car’s adhesion to the road.