Audi RS 6

The Audi RS 6 is a high-performance variant of the Audi A6 range, produced by the high-performance subsidiary company Audi Sport GmbH, for its parent company Audi AG, a subsidiary of the Volkswagen Group, from 2002 onwards.
The first and second versions of the RS 6 were offered in both Avant and saloon forms. The third and fourth generations are only offered as an Avant.

Overview

The "RS" initials are taken from the – literally translated as "racing sport", and is Audi's ultimate 'top-tier' high-performance trim level, positioned a noticeable step above the "S" model specification level of Audi's regular model range line-up. Like all Audi "RS" models, the RS 6 pioneers some of Audi's newest and most advanced engineering and technology, and so could be described as a halo vehicle, with the latest RS 6 Performance having the most powerful internal combustion engine out of all Audi models, with the same power and torque as the physically larger Audi S8 Plus. Unlike the A6 and S6, however, the RS 6's engines in the C5 and C6 iterations have not been shared with any other vehicle in Audi's lineup. However, for the C7 generation, the Audi RS 6 has the same 4.0 L bi-turbo V8 engine as the Audi RS 7, with both being positioned at the top of the Audi S and RS range, detuned variants of the same engines are found in the Audi S8, Audi A8, and Audi S6.
Based on the A6 platform, the RS 6's engines are front-mounted and longitudinally oriented, while the transmission is mounted immediately at the rear of the engine in a longitudinal orientation, in the form of a transaxle. Like all S and RS models, the RS 6 is only available with Audi's 'trademark' Torsen-based quattro permanent four-wheel drive system.
The C5 RS 6 was the fourth model to come out of Audi's private subsidiary company, "quattro GmbH". The first was the Audi RS 2 Avant, from a joint venture between Porsche and Quattro GmbH for the Audi marque. The second was the Audi C4 S6 Plus, produced from April 1996 to July 1997. The third was the 2000 Audi B5 RS 4; the fifth was the 2005 Audi B7 A4 DTM Edition saloon, and the sixth was the 2006 Audi B7 RS 4. The seventh and current Quattro GmbH model is the latest [|Audi C6 RS 6].
Production of the original [|Audi C5 RS 6] began in June 2002 and ended in September 2004. The second Audi C6 RS 6 was introduced at the 2007 Frankfurt Motor Show. The original RS 6 was the first Audi RS variant exported to North America, while the C6 and C7 RS 6 were only sold in Europe, with the C8 RS 6 again being offering in North America.
Main rivals for the Audi RS 6 are the BMW M5 and Mercedes-Benz E 55/E 63 AMG.

C5 (''Typ'' 4B, 2002–2004)

The original Audi C5 RS 6 Quattro was the top-of-the-line user of the Volkswagen Group C5 platform, and was initially available as a five-door five-seat Avant - Audi's name for an estate or station wagon. A four-door five-seat saloon/sedan followed shortly after the launch of the Avant. Derived from the Audi C5 S6, the RS 6 also shares the aluminium structure from the firewall and forward with the C5 A6s with V8 engines. It was manufactured from July 2002 through to September 2004.
Official performance figures for the Avant, whilst consuming the recommended high octane 98 RON "Super Plus" unleaded petrol indicate the 0- dash would be completed in 4.6 seconds, reaching in 17.8 seconds. Official figures state an electronically limited top speed of, although most "RS" owners report that the speed limiter is rather liberal on all RS cars, with genuine 'limited' top speeds of being possible to achieve. Using a lower octane-rated petrol, such as the standard 95 RON "Premium" unleaded will reduce the engine power output, and have logical reduction in performance.
Luggage capacity, measured according to the VDA block method in the Avant ranges from, to with the rear seats folded down. For the saloon, the boot holds.

C5 powertrain

For the C5 RS 6 powertrain detail, the engine is an all-aluminium alloy twin-turbocharged, double overhead camshaft, 5 valve per cylinder version of Audi's 4.2-litre 90° V8 petrol engine, developed and manufactured in Germany and the UK by quattro GmbH and Cosworth Technology. With the addition of the two turbochargers, the power output of the V8 engine increased to at 5,700 to 6,400 rpm, and of torque. The combination of the 4.2-litre V8, variable inlet valve timing, and twin turbochargers give the RS 6 an exceptionally wide power band, with peak torque available from 1,950 to 5,600 rpm.
Further detail includes fully sequential electronic multi-point fuel injection with intake manifold fuel injectors, mapped direct ignition system with solid-state high voltage distribution using eight individual single-spark ignition coils and NGK longlife spark plugs, and three knock sensors. Engine management uses a Bosch Motronic ME 7.1.1 engine control unit, which controls all functions of the engine operation; including fuel delivery, ignition system, valve timing, emissions control systems, and torque reduction control—the latter operating in conjunction with the Bosch ESP 5.7 Electronic Stability Programme, as part of the "Anti Slip Regulation" traction control system. The engine is compliant with the European Union Euro3 standard, and includes two close-coupled primary catalytic converters, two underfloor main CATs, and four heated oxygen sensors which manage the cylinder bank selective lambda control. This results in a CO₂ emissions rating of 350 g/km for the Avant and saloon in standard configuration.
It has an electronically controlled five-speed ZF 5HP24A tiptronic automatic transmission , with lock-up torque converter in all forward gears. It has "hill-detection" capability, and despite many press articles stating that the gearbox was programmed to "blip" the throttle for downshifting gear changes, no UK owners have ever found this feature to be present. The transmission control unit ECU incorporates "fuzzy logic" with its "Dynamic Shift Programme", with the shift pattern adapting to suit individual driving styles. 'Tiptronic' manual control can be achieved with either the floor-mounted gear shift lever or the steering wheel-mounted 'paddles'.
The RS 6 was only available with Audi's Torsen-based Quattro permanent four-wheel drive, utilising the Torsen T-2 dynamic 'automatic torque biasing' centre differential, a modified unit which was being used in the 6.0-litre W12-powered Audi D3 A8. The torque from the engine is first routed from the gearbox output shaft to the Torsen centre diff, and then automatically divided and apportioned between the front and rear axles.
The front and rear axle differentials are a conventional "open" type but utilise an "Electronic Differential Lock". EDL is an integrated additional function of the Bosch Electronic Stability Programme system, and works by monitoring and comparing the individual wheel speeds across an axle, and braking an individual wheel which is sensed to have lost traction, thus transferring torque across the axle to the wheel/tyre which does have grip. "Anti-Slip Regulation", more commonly known as traction control system completes the Bosch ESP-related driver aids.

C5 suspension and steering

Utilising the same fully independent four-link front suspension, and double wishbone rear, as its related A6 and S6, the RS 6 was lowered by, with a 30% stiffer spring rate, and 40% increased compression damping. The RS6 also served as the debut model for Audi's "Dynamic Ride Control" system. The DRC system is mainly mechanical, and uses a pump to provide additional pressure to individual dampers during cornering, acceleration or braking; to counteract rolling and pitching. The system can adjust the stiffness at each individual damper constantly; to maintain both a comfortable ride on straight roads, and a high level of poise and grip when cornering hard, accelerating, or braking. The DRC's main advantage is that it operates without the need for complicated electronics, as required in similar systems from Mercedes-Benz and other competitors. Its main drawback is that the DRC dampers have been known to fail, which can affect the handling and ride quality of the vehicle; some owners have reported needing multiple replacements of faulty DRC units and many drivers have opted to replace the system with simpler and more reliable aftermarket coil-over suspension.

C5 brakes, wheels and tyres

The front brakes feature fixed Brembo 8-piston monoblock brake calipers, working with radially vented and cross-drilled brake discs, sized at in diameter, by thick. The rear features single-piston floating ATE calipers with integrated cable-operated parking brake mechanism, mated to radially vented disc and cross-drilled, sized by. Front and rear brake calipers are finished in a high-gloss black paint, with the fronts incorporating the Audi "RS" logo. Both front and rear discs are held in by metal pins to the lightweight disc hub, and allow of lateral thermal expansion from the hub centre.
Bosch ESP 5.7 Electronic Stability Programme, with Anti-lock Braking System, Electronic Brakeforce Distribution, and Brake Assist was standard fitment.
There were a total of three original equipment manufacturer wheel and tyre types available with the RS 6. In Europe and elsewhere, 19-inch wheels were standard, with an optional 18-inch package. In the U.S. market, the 18-inch package was the only available offering. An 18-inch winter package, with Dunlop SP Winter Sport M3 tyres was universally available.

C5 RS 6 Plus

Between April 2004 and September 2004, there was a final limited run of an even higher-performance RS 6, named the Audi RS 6 Plus. This had an increased engine power output, and produced at 6,000-6,400 rpm, with the same of torque at 1,950-6,000 rpm. This engine was also developed and manufactured in the UK by Cosworth Technology. The additional performance was achieved with a new engine control unit, and two additional coolant radiators behind the side-mounted intercoolers. Official performance figures indicate the discipline of sprinting from standstill to in 4.4 seconds. The RS 6 Plus carries on to reach in 20.36 seconds, and has an official top speed of.
The RS 6 Plus came with Dynamic Ride Control as standard, and also included a no-cost option of "Sports Suspension Plus", which lowered the standard sports suspension by a further over the standard RS 6. A revised steering rack, with a reduced ratio of 14.3 for firmer steering feel was included, and resulted in a turning circle of. The brakes now included cross-drilled discs. The wheels were only available in the 9Jx19-inch '5-arm design' alloys, finished in "anthracite", with tyres.
The car was available only as an Avant and was sold only in European markets. Visual differences for the RS 6 Plus included the "black optic pack", which consisted of black finish to the framing of the radiator grille, exterior window trims, tailgate lower trim, roof rails, and exhaust tailpipes. It quickly sold out once it was released. The last three digits of the Vehicle Identification Number are reproduced on a plaque inside the car, displayed on the centre console.