The CHASSIS: a new level of driving dynamics

Thanks to quattro drive with RS torque splitter, two RS 3-specific drive select modes, a new brake system, and semi-slick tires, the Audi RS 3 reaches a new level in terms of driving dynamics. Further extensive body and chassis modifications transform the model into a top‑of‑the-line sports car suitable for everyday use.

A matter of lateral: the RS torque splitter

The new Audi RS 3 is the first Audi model with a torque splitter. This technology makes fully variable torque distribution between the rear wheels possible. Unlike the previous rear axle differential with upstream multiple disc clutch package, the torque splitter uses one electronically controlled multiple disc clutch on each of the respective drive shafts. This ensures that the right amount of torque is optimally and continuously distributed along the rear axle.

During dynamic driving, the torque splitter increases torque delivered to the outer rear wheel with the higher wheel load, which significantly reduces the tendency to understeer. In left-hand curves, it guides the drive torque to the right rear wheel, in right-hand curves to the left rear wheel, and when driving straight ahead, to both wheels. The difference in propulsive forces means that the new RS 3 turns into curves even better and follows the steering angle more precisely. This results in optimal stability and maximum agility – especially when cornering at high speeds. The torque splitter compensates for oversteer by directing the torque to the wheel on the inside of the curve or to both wheels. If the driver takes his or her foot off the accelerator, the engine’s drag torque is also distributed along the rear axle. When coasting, controls are also in place to maintain driving agility and stability. If faster deceleration is initiated via the brake pedal, both of the torque splitter’s clutches are opened.

In order to maximize its effect, the torque splitter has its own sensor system. Each of the two multiple disc clutches has its own control unit, which use the electronic stabilization control’s wheel speed sensors to measure the wheel speeds. Other influencing factors include longitudinal and lateral acceleration, the steering angle, the position of the gas pedal, the selected gear, and the yaw angle, i.e. the rotational movement around the vertical axis.

On the one hand, the torque splitter increases safety in everyday use, and on the other it enables faster lap times on the racetrack. Frank Stippler, Audi Sport racing and development driver, proved the latter on the 20.832-kilometer Nürburgring-Nordschleife in June 2021. At the wheel of the RS 3 Sedan, he set a new record in the compact segment with a lap time of 7:40.748 minutes. 

Racetrack and drift mode: new driving profiles in Audi drive select

The Audi drive select dynamic handling system boasts two completely new RS 3-specific modes: RS Performance for the racetrack and RS Torque Rear, a drift mode for use on closed roads. In addition to the familiar comfort, auto, dynamic, and RS Individual modes, the RS 3 also features the efficiency mode for the first time. Depending on the selected mode, the characteristics of important powertrain and chassis components change from an emphasis on comfort to highly dynamic to even optimized specifically for the racetrack. In addition to the torque splitter, Audi drive select also has an effect on the engine and transmission characteristics, steering assistance, electronic stabilization control, the exhaust flaps and, optionally, the adaptive suspension. Different characteristic curves for each of the aforementioned systems create a broad range of driving experiences.

The ultimate in driving dynamics can be experienced in dynamic mode and in the new RS 3-specific RS Torque Rear mode. In dynamic mode, all of the components are configured for a sporty ride. The driver feels this in a more direct steering response and particularly agile handling for dynamic driving with a clearly perceptible engine sound.

This mode tends to transmit as much drive torque as possible to the rear axle. The gearshifts of the S tronic are shorter, acceleration even sportier.

This is taken to perfection by the RS Torque Rear mode, which enables controlled drifts and sporty driving with lateral dynamics. It is specially designed for closed roads. In this mode, an oversteering driving behavior is generated, with up to 100 percent of the drive torque directed to the rear ending up at the wheel on the outside of the curve – up to a maximum of 1,750 newton meters. In addition, the engine’s characteristic curve is also modified in RS Torque Rear – and is even more pronounced than in dynamic mode. The same applies to RS Performance mode, which is specially designed for the racetrack. In both modes, the idle speed has been increased even further compared with the dynamic profile to enhance off-the-line performance. The throttle response is even more direct and has a distinctive load shift. Moreover, drivers experience very late upshifting and early downshifting as well as optimal control of the linear accelerator at the apex of a curve. In addition to the specific engine and transmission setup, RS Performance mode is also specially calibrated to the Pirelli P Zero “Trofeo R” semi-slick tires, which are optionally available factory-mounted for the first time. There, the torque splitter ensures the most neutral handling possible with little oversteering or understeering in different driving situations. This makes early acceleration possible upon exiting a curve, enabling faster lap times. RS Performance mode is equipped with two setups for different tracks – one is adjusted for comfort on uneven tracks like the Nordschleife, where minimizing vertical excitation while maintaining high lateral dynamics matters, and the other is a sporty setup for even racetracks like the Hockenheimring. The steering and electronic stabilization control can also be set to two predefined characteristic curves in RS Performance mode.

In the auto driving profile, the mode for everyday driving, torque distribution is balanced, which means that the RS 3 neither understeers nor oversteers. The engine and transmission characteristics are adapted to this. In comfort mode, steering is somewhat smoother, the sound of the five-cylinder is more subdued, and the damping behavior is softer. In this mode, the torque splitter ensures that the engine power is distributed to all four wheels, with priority given to the front axle. The latter also applies to the consumption-optimized efficiency mode. This mode contains a flatter accelerator pedal characteristic curve. Torque and power are limited to 80 percent, while 100 percent is available upon kickdown. This mode also makes it possible to coast at idle with the engine on. In RS Individual mode, drivers can configure up to six systems separately within their predefined characteristic curves.

For outstanding handling: stiffened components

The body of the new Audi RS 3 plays a key role in the compact sports car’s agile handling. It is ten millimeters lower than the Audi S3 and 25 millimeters lower than the A3. This lowers the vehicle’s center of gravity further towards the road. At the front, the RS 3 is equipped with a McPherson strut axle with RS 3-specific pivot bearings that allow just under one degree more negative wheel camber compared to the A3. This increased tilt towards the road surface, i.e. the greater angle between the wheel plane and the vertical, improves steering response in addition to greater lateral control, i.e. more grip and dynamics when cornering. In conjunction with the stiffer wishbones compared with its predecessor, the RS 3 is even more agile. The rear axle features a four-link design with separate spring/shock absorber arrangement, subframe, and tubular stabilizer bar. The RS-specific tubular stabilizer adapted to the torque splitter has a higher spring rate than in the previous model –for optimum performance. The wheel camber is almost half a degree larger than on the A3. All of these components contribute to the increased lateral dynamics, as do the stiffer wheel carriers.

Precision engineering: the RS sports suspension

The standard RS sports suspension features newly developed shock absorbers and a valve system both specific to the RS 3. The setup of the springs and shock absorbers is markedly stiff. The specially fine-tuned valves ensure that the shock absorbers exhibit a particularly fine response as part of the rebound and compression characteristics. This allows the suspension to respond to the respective driving situation even faster and with greater precision.

The RS sports suspension can be ordered with optional adaptive damper control. It continuously and individually adjusts each shock absorber to the road conditions, the driving situation, and the mode selected in Audi drive select. The three characteristic curves comfortable, balanced, and sporty provide a clearly perceptible spread of the shock absorber characteristics. The ideal damping force is calculated within milliseconds. To do this, sensors measure the vertical acceleration of the body and the movement of the individual wheels relative to it. This results in increased dynamics and excellent driving stability with even greater comfort compared to the RS sports suspension. In RS Individual mode, the shock absorbers can be configured according to individual requirements and the road conditions within the three characteristic curves. In RS Performance Mode, there is a specific comfort setting for the shock absorbers that minimizes excessive vertical excitation while maintaining excellent lateral dynamics – this is particularly suitable for racetracks with uneven surfaces, such as the Nurbürgring-Nordschleife.

Newly developed: six-piston steel and ceramic brake system

Increased dynamics also means higher demands placed on the brakes. This is why the RS 3 features a newly developed and larger six-piston steel brake. Its internally ventilated and drilled discs measure 375 by 36 mm at the front and 310 by 22 mm at the rear. This means they are five millimeters larger in diameter and are also more stable than in the predecessor model.
A 19-inch ceramic brake system measuring 380 by 38 millimeters at the front with a pedal characteristic curve specially adapted to the brake booster is optionally available. The high-performance brake system weighs another ten kilograms less than the steel brake and offers outstanding thermal stability, particularly in dynamic driving situations.

New air control elements in front of the wishbones channel air specifically into the wheel well, thus improving brake cooling. They improve the brakes’ cooling time by 20 percent. This more quickly reduces peak temperatures during hard braking while pedal feel remains the same. In addition, it also reduces brake pad wear, which are 15 percent larger and copper-free. Those who opt for the ceramic brakes can choose between gray, red, or blue brake calipers. Those who prefer the steel version can order red calipers instead of the black ones.

Premiere for factory-equipped semi-slicks: the tires

The RS 3 comes standard-equipped with 265/30 front and 245/35 rear tires, each ten millimeters wider than the optional mixed-sized tires on the predecessor model. They are mounted on 19-inch cast wheels in a 10-Y spoke design. Alternatively, 5‑Y spokes are available – the embodiment of true racing design. Both wheels feature the RS branding. The standard tires are optimized in terms of rolling resistance thanks to modified tread geometry and a new rubber compound. Despite the increased width, the weight has remained the same. For particularly sporty drivers, Audi is offering Pirelli P Zero “Trofeo R” semi-slick tires, which are available factory-mounted for the first time. They are designed specifically for driving on racetracks, but are also approved for use on public roads. In addition to a newly developed asymmetric tread, the tires also feature a specific rubber compound. This combination delivers exceptional grip in dry conditions. Stability and lateral support were increased once again.

On board for the first time: the modular vehicle dynamics controller

Following its initial use in the A3 and S3, the modular vehicle dynamics controller (mVDC) now also ensures that the chassis systems interact more precisely and more quickly in the RS 3. As a central system, it captures data from all components relevant to lateral dynamics, thus ensuring that they interact more precisely and more quickly. The mVDC synchronizes the torque splitter’s two control units and the adaptive dampers for high-precision steering and handling. It also influences the wheel-selective torque control and thus interacts with the newly developed six-piston steel brake or the optional RS ceramic brake. The vehicle dynamics controller demands more or less torque from the torque splitter, depending on the requirements. This further increases agility – especially on winding roads.

Later intervention: the electronic stabilization control system

The electronic stabilization control (ESC) system in the RS 3 has been specifically adapted to the torque splitter and the new RS 3 driving modes. The ESC’s sport mode, for example, is configured for the highest possible performance with respect to the interaction between the engine, transmission, quattro with RS torque splitter, and suspension. It provides more driving enjoyment by engaging the ESC control later. If you hold down the button in the center console for at least three seconds, the ESC can also be switched off completely – useful and helpful on closed roads, for example, if you want to fully experience the Torque Rear mode.

RS-specific tuning: the progressive steering system

The RS 3 comes with electromechanical progressive steering standard. It varies the ratio depending on the steering angle – as the steering angle increases, the ratio becomes smaller and the steering more direct. On the one hand, this enhances driving dynamics and, on the other, increases driving comfort by reducing steering effort. The sportier setup, RS-specific characteristic curves, and a more direct steering response – adapted to the suspension and tires – also ensure that the progressive steering system maintains close contact with the road surface, even when cornering at high speeds. In addition, it provides speed-dependent assistance for a precise steering feel at high speeds and smooth steering when parking or maneuvering. The basic setup can be varied via Audi drive select in the three characteristic curves comfortable, balanced, and sporty.

Safe and quiet: the body

The RS 3 Sportback weighs 1,570 kilograms empty without a driver, the RS 3 Sedan 1,575 kilograms. The passenger compartment is made of hardened steel materials. Before forming, they are heated to almost 1,000 degrees Celsius in a furnace and then cooled to around 200 degrees directly afterwards in the water-cooled press die. This extreme temperature shift results in high tensile strength. These kinds of hardened steel materials are relatively thin and are therefore very light in relation to their strength properties. These steels are used in the transition from the front end to the passenger cell, in the A-pillars, the B‑pillars, the roof arch, the center tunnel, the rocker panels, and in the floor panel. They account for around 26 percent of the body. High-strength and ultra-high-strength steel grades are also used for the longitudinal members and in the floor of the passenger compartment. The engine hood is made of aluminum. An aluminum profile behind the front apron serves as a crash absorber.

The acoustic glass used for the front windshield comes standard. Other measures such as wheel arch liners made of fleece material reduce interior noise, even at high speeds. The insulation behind the pillar trim, behind the instrument panel, and in the luggage compartment further minimizes noise.

All terms marked in the text are explained in detail in the technology lexicon at www.audi-mediacenter.com/en/technology-lexicon. The equipment, data and prices specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.