The sports car for everyday use offers exhilarating dynamics. Its handling is uncompromisingly precise; its reactions are virtually instantaneous, and its stability guarantees maximum driving safety. The newly developed electromechanical power steering connects the driver with the road to provide sensitive, well-differentiated feedback.
Steering boost changes as a function of speed. The electric motor integrated into the steering gear consumes no energy when driving straight ahead, thus lowering fuel consumption by as much as 0.3 liters per 100 km. The steering gear is very compact thanks to the concentric arrangement of the steering rack and servo drive.
The electromechanical power steering system’s ratio of 16.3:1 is sporty and direct. The low-mounted steering gear communicates the steering input to the wheels over the shortest possible distance via the track rods.
The Audi RS 4 Avant has a turning circle of approximately 11.9 meters (39.04 ft). The steering works closely together with the optional assistance system Audi active lane assist. When braking on a surface that is slippery on one side, the system helps the driver by facilitating the proper corrections and inhibiting improper steering movements.
All major suspension components are made of aluminum, which greatly reduces the unsprung masses. The five-link front suspension processes the longitudinal and lateral forces separately. The aluminum frame to which it is linked makes the front end extremely rigid. The springs and dampers of the track-controlled trapezoidal link rear suspension are separated to improve response behavior. The links are mounted on a steel subframe on elastic bearings.
Decidedly taut: the setup
The Audi engineers have given the new RS 4 Avant a strictly dynamic setup. Stiff bearings provide for sporty elastokinematics, and the stabilizer bars are thicker than in the volume A4. The shock absorbers are stiffer, and the body has been lowered 20 millimeters (0.79 in). Audi also offers the sport suspension plus with Dynamic Ride Control (DRC) as an option. It reduces all body movements purely mechanically and thus without any lag, and is compact and lightweight.
The principle behind the DRC is impressively simple. The diagonally opposed pairs of shock absorbers are linked by hydraulic lines and a central valve. When cornering at speed, the valves regulate the oil flow in the shock absorber of the deflected outside front wheel almost immediately. They increase the support provided and reduce lateral tilt. The system is combined with variable damper control, which can be switched between three stages using the standard Audi drive select dynamics system.
In addition to the sport suspension plus and the sport differential, both of which are optional, Audi drive select also incorporates the electromechanical power steering, the seven-speed S tronic, the engine’s throttle valves and the sound flap in the exhaust system.
The driver can vary the function of these systems between the modes comfort, auto and dynamic. And if the car is equipped with an MMI navigation system, there is also a fourth mode which can be configured within certain limits by the driver.
Another optional component of Audi drive select is dynamic steering, whose characteristics have been specially tuned in the RS 4 Avant. The key component is a high-tech superposition gear in the steering column. It steplessly varies the steering ratio as a function of speed, from very direct when maneuvering to indirect on the highway. At the cornering limit, the dynamic steering countersteers with minimal pulses, making the handling even more dynamic, fluid and safe. It prevents the car from pulling when braking on a surface that is slippery on one side.
The Audi RS 4 Avant comes standard with ten-spoke wheels made of machine-polished forged aluminum. The 9J x 19 wheels are fitted with 265/35-series tires. Audi offers optional 20-inch wheels in three variants with 265/30-series tires, with two featuring a machine-polished, titanium-look finish. Winter wheels featuring the same dimensions are available. All tires have been optimized for rolling resistance without compromising handling or braking.
Powerful and lightweight: the brakes
Large wave-design discs are mounted behind the large wheels. Discs measuring 365 millimeters (14.37 in) in diameter and 34 millimeters (1.34 in) thick are mounted on the front axle; the rear axle features discs measuring 324 x 22 millimeters (12.76 x 0.87 in). The friction rings are internally vented and perforated. Their new wave-like outer contour reduces the overall weight of the brake system by roughly 2.5 kilograms (5.51 lb). Stainless steel pins connect the steel friction rings to the aluminum brake caps. This concept borrowed from racing reduces tensions, quickly dissipates the heat and prevents the transmission of temperature peaks.
The monoblock calipers painted high-gloss black and bearing RS logos are also made of aluminum. The front calipers each have eight pistons; single-piston floating calipers are mounted on the rear axle.
For the front axle, Audi offers the option of 380 millimeter (14.96 in) perforated carbon fiber ceramic discs and six-piston calipers in Anthracite Gray. The base material is silicon carbide, a material with a diamond-like crystal structure in which high-strength carbon fibers are embedded.
The geometry of the cooling channels quickly dissipates the heat. Titanium bolts connect the friction rings to the forged aluminum caps. The ceramic discs are practically fade-free, extremely robust, powerful and durable. Altogether they weigh 4.5 kilograms (9.92 lb) less than the steel discs despite their larger size.
The ESC stabilization control has been specially configured for the dynamic profile of the new Audi RS 4 Avant. With the touch of a button, the driver can select the Sport mode that deactivates the engine interventions and thus permits spectacular but safe drifts when accelerating. The ESC can also be deactivated entirely for particularly dynamic driving. A subfunction of the system is the optional Audi hold assist. It makes it easier to start off on grades by maintaining the pressure in the system after the brake pedal is released.
The equipment and data specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.