05-09-2005
New dimensions in driving dynamics combined with innovative ideas – plus exciting styling and a level of equipment that lives up to even luxury-class standards: the new Audi RS 4 combines the latest high-performance product from quattro GmbH in a thoroughbred sports saloon with supreme everyday driving qualities in the premium segment. The RS 4 is the new top-of-the-range model in the A4 series, a development all-new from the ground up.
Numerous technical innovations – many of which hail from motorsport – give the new Audi RS 4 its unique class and character. These features include the high-revving concept now being introduced for the first time in a production Audi, innovative FSI technology, as well as the latest generation of quattro drive with asymmetric/dynamic torque distribution. Developing a maximum output of
420 bhp, the V8 revs up to a speed of 8,250 rpm. With its displacement of
4,163 cc, this outstanding engine breaks through the magic barrier for a production saloon of 100 bhp per litre. The highly compact power unit reaches its peak torque of 430 Nm at 5,500 rpm. 90 percent of the total torque is available between 2,250 and 7,600 rpm. The result is excellent pulling power at all times, enabling the driver to drive in a relaxed style without frequent gear changes.
Audi's RS 4 saloon employs groundbreaking FSI technology. The petrol direct-injection unit delivers enhanced power output based on more efficient combustion of the fuel/air mixture. The engine is also responsive. The performance of the RS 4 clearly demonstrates these enhancements: it reaches the 100 km/h mark in 4.8 seconds, and 200 km/h in 16.6 seconds. Top speed is limited electronically to 250 km/h.
The efficiency of FSI technology has already been demonstrated impressively in Audi’s four-time Le Mans winner, the Audi R8.
Another key requirement for the developers was an optimum power-to-weight ratio. It was important that the Audi RS 4 should weigh not a gram too many. Practically every part was checked in terms of its weight. The front wings and the bonnet are therefore made of aluminium, as are most of the chas¬sis components. The specially designed RS bucket seats are not only very light, but also offer excellent body support.
The result is a power-to-weight ratio of just 3.93 kilos per bhp – a sports car-like accomplishment which would have been inconceivable for a mid-size saloon just a few years ago.
New generation of quattro drive
The challenge is to transfer all this power to the road in the best way possible. For the last 25 years, Audi’s answer to these special demands has been its quattro drive. The latest generation of Audi’s permanent four-wheel drive, which is featured for the first time on the RS 4, offers a 40 (front) to 60 (rear) asymmetric/dynamic torque distribution ratio and the self-locking Torsen centre differential and, along with its sports suspension, has propelled the RS 4 into entirely new dimensions in driving dynamics. Indeed, Audi quattro technology still provides traction when other drive concepts have long since reached their limits. quattro drive is further enhanced by DRC (Dynamic Ride Control) which significantly reduces both the rolling and pitching motions of the vehicle.
The brakes, too, represent new dimensions in their innovation. The 18-inch format provides optimum deceleration. The perforated ventilated brake discs at the front measure 365 millimetres in diameter, with similarly perforated ventilated brake discs at the rear in 324-millimetre diameter. Flow-enhanced ventilation geometry incorporating NACA jets on the underbody of the car ensures optimum cooling of the brakes.
As a result, brake fading is significantly reduced even under extreme loads, such as on the race track.
The latest generation of ESP has been modified specifically to suit the special properties of the high-performance RS 4. Its interventions are now later and shorter. It is also possible to disable the ESP in two stages. In the first stage only the traction control (ASR) function is disabled; the other ESP functions remain fully active. In the second stage the ESP is completely deactivated, including the traction control. All electronic control then ceases. The integrated dry braking function provides additional safety in wet weather. When the road is wet the brake pads are applied to the brake discs at regular intervals, unnoticed by the driver, and the brakes are dried.
Design
The RS 4 features racing technology in plain clothes. While many of its features look similar to the new Audi A4, the RS 4 is far more than just a fast derivative of Audi’s successful mid-size saloon. The car is an almost entirely brand-new development tailored to the highest performance requirements.
The single-frame radiator grille, the rear end with its distinctly horizontal styling and the sculpted sides all prove that the RS 4 is truly a member of the A4 family. However, the radiator grille in diamond look, the additional air inlets in the front end as well as wheels developed specifically for the RS 4 clearly differentiate the car from a standard Audi A4. The newly designed rear apron encompassing two large tailpipes as well as the discreet but effective spoiler integrated into the boot lid and the rear side panels all bear clear testimony to the saloon’s dynamic potential.
Compared with the Audi A4, the car's trim has been lowered by 30 millimetres. The developers have also widened the front and rear track, resulting in a widening of the vehicle body. However, all these modifications to the body of the car are not only significant in terms of design, they are also functional in character.
Inside, the RS 4 combines the functionality of a sports car with the luxurious ambience so typical of all Audi models. Leather, aluminium, and carbon are the predominant materials. But at the same time the RS 4 comes with all the additional qualities typical of a genuine sports car.
This becomes clear as soon as you sit in it. The RS bucket seats, with their high side sections, offer firm hold. They also have an additional feature. By pressing buttons on the seat the side sections can be inflated to mould perfectly to the driver's anatomy. The flat-bottomed RS sports steering wheel and the engine start button on the centre console are also clearly reminiscent of motorsport, as indeed are the aluminium pedals.
The Sport button on the steering wheel delivers even more dynamic performance when required. The accelerator characteristic changes progressively, so the engine is perceived to respond sooner. A flap in the exhaust system opens to provide the RS 4 with an even sportier sound. As an additional feature, the side sections of the bucket seats are inflatable. This enhances the side hold. The steering wheel also provides buttons to operate the driver information system.
Equipment
Driving the Audi RS 4 means driving a sports car without missing out on any of the comforts. The RS 4 therefore comes with virtually all the features already boasted by the Audi A4. Apart from a wide range of safety com¬ponents, this also means deluxe automatic air conditioning, central locking with remote control and electric front windows. Further features of the RS 4 include the Audi parking system at the front and rear, the concert radio system as well as sports suspension with variable damping (DRC). Furthermore, RS 4 drivers can also opt for even higher levels of comfort in features such as the Audi navigation system plus or the adaptive light dynamic cornering lights.
Text and photos courtesy of Audi AG
