Audi developed a transmission for the RS6 based on the gearbox found in the 12-cylinder A8, but this Tiptronic five-speed was fitted with ratios and controls specific to the RS6. In the driver-selected "sport" setting, gears are held longer on upshifts and engage at higher revs when downshifting. Depending on the level of lateral acceleration, the transmission management system can even adjust shift points, thus avoiding any "hunting" during cornering.
The RS6 driver can also operate the transmission manually in two ways, the conventional method by pressing the gear selector forward or backward, and the racing-inspired option of using paddles mounted on the backside of the steering wheel, the left paddle for downshifts and the right for upshifts. These paddles can be called into play anytime, the driver's input overriding the current transmission setting. Should the paddles go unused for a prolonged period, the tranny will default back into auto mode. It's like having a little Audi tranny elf in the car with you.
This exceptional transmission is made even better by Audi's DSP (Dynamic Shift Program) with hill-detection capability. DSP offers more than 200 shift patterns, designed to match driver characteristics with driving conditions, while hill detection prevents gear hunting on inclines. This is the finest of the new breed of "smart transmissions" I've driven, providing the perfect blend of control with transparent computer assistance. For the first time, I was perfectly content in a performance car that didn't have a manual gearbox.
The RS6 rides on the same base suspension as the S6, although springs rates were increased 30%, the shock rates 40% and the chassis situated 25mm lower. The underpinnings benefit from aluminum swivel bearings and control arms on the four-link front suspension, and double A-arm rear suspension. Larger anti-roll bars in front and rear help maintain high-speed stability.
The big news, however, is Audi's Dynamic Ride Control. This is the first Audi to offer an active suspension system, which was developed around diagonally connected, hydraulically damped shock absorbers. By continually monitoring and adjusting the hydraulic pressure at each corner, DRC limits body roll and pitch. The single-tube shocks on the same side of the car are mechanically linked to the dampers on the other side via separate oil lines, each with a central valve. When the suspension is compressed on one side, the damper characteristic is modified in such a way as to counter rolling or pitching movements. A central reservoir works to balance hydraulic pressure when both the front or rear shocks are under load, like hard braking. Interestingly, DRC is operated purely through mechanical hydraulics-no fancy computer wizardry here. It's an elegant solution and typical of Audi's longtime philosophy: progress through technology rather than technology for technology's sake. Of course, you'll also find EDL (Electronic Differential Lock), ESP (Electronic Stabilization Program), EBD (Electronic Brake-force Distribution) and ABS on the RS6, although with re-tuned parameters befitting the car's god-like performance.
Audi rummaged through its motorsports parts bins and developed a new brake system unique to the RS6. It's comprised of 14.4-in. front discs and 13.2-in. rear discs, in a newly designed composite configuration. A cast friction ring is fixed to the aluminum brake-disc hub by 14 pins, this "floating" arrangement improving the stability of the discs, particularly when exposed to extreme loads and high temperatures. The ventilated and cross-drilled front discs are gripped with gigantic Brembo calipers featuring eight pistons and four large pads. The rears, also ventilated and cross-drilled, are single-piston floating units. These amazing anchors can bring the 2-ton Audi from 62 to 0 mph in 2.6 sec. It's race-car technology, beautifully applied.