BMW Tuning Cars: Audi S6

The Audi S6 is a high-performance version of the Audi A6, an executive car produced by German automaker Audi. It went on sale in 1994, shortly after the "A6" designation was introduced, replacing the "100" nameplate. The original S6 (Ur-S6) was largely the same car as the outgoing, original Audi S4 (C4) (Ur-S4), with the only visible differences being new body-cladding and badging. The S6, like all Audi "S" models, is fitted as standard with Audi's trademark quattro four-wheel drive (4WD) system, the S6 using the Torsen-based permanent 4WD. Audi was restructuring their model lineup in early and mid-1990s, and in late 1994, began selling the fifth generation (C4) Audi 100 model, re-badged as the Audi A6. Wanting to keep a sports-saloon in their lineup, the company made small revisions to what was previously known as the Audi S4, renaming it the Audi S6; the S4 name would eventually be re-used for a completely different model derived from Audi's smaller Volkswagen Group B platform-based Audi A4. As this was the first S6 model from Audi, it is commonly referred to as the Ur-S6, derived from the German augmentive, "Ursprünglich" (meaning: original). It was available as both a saloon/sedan (typ 4A5), and an "Avant" (typ 4A9) (estate/wagon) to European and United States customers, but only as a saloon in Canada, Asia and Australia. Audi's trademark "procon-ten" safety system was standard fitment.

A higher performance Audi RS6 was also available for a limited timescale. It was built by AUDI AGs' high performance private subsidiary company - quattro GmbH. It used a twin-turbo ("biturbo") version of the 4.2 litre V8 engine (identification code: BCY). Motive power figures were 331 kilowatts (450 PS; 444 bhp) at 5,700 to 6,400 revolutions per minute (rpm), with torque rated at 560 newton metres (413 ft·lbf) from 1,950 to 5,600 rpm. Transmission was a five-speed tiptronic automatic. Roadwheels and tyres were upgraded to 255/40 ZR18 99Y XL, or 255/35 ZR19 96Y XL (5/15 arm design), and there was the "Dynamic Ride Control" (DRC) system available for the suspension, which featured diagonally interlinked shock absorbers, to give better body control during extreme cornering, acceleration and braking. Compared to standard S6, the suspension was lowered by 20 millimetres (0.79 in). The brake discs were ventilated and upgraded to 365 millimetres (14.37 in) at the front and 335 millimetres (13.19 in) at the rear. The latest Audi S6 quattro model (Typ 4F) was introduced at the 2006 North American International Auto Show in January. It is based on the current C6 Audi A6, and uses the Volkswagen Group C6 platform, and is available in saloon/sedan and Avant (estate/wagon) bodystyles. Factory production started in June 2006.Motive power in the C6 S6 powertrain features an all-aluminium alloy 5,204 cubic centimetres (317.6 cu in) Fuel Stratified Injection (FSI) 40-valve (four valves per cylinder) 90° V10 petrol engine (parts code: 07L, identification code: BXA). Compared to the similar, but completely unrelated 5.0 litre V10 engine found in the Lamborghini Gallardo, a longer stroke and wider bore increases the displacement of the engine, and produces more torque at lower revs, making it more suitable for the larger and heavier Audi executive passenger car. It produces a 320 kilowatts (435 PS; 429 bhp) at 6,800 revolutions per minute (rpm), and 540 newton metres (398 ft·lbf) of torque between 3,000 to 4,000 rpm. It utilises twin chain-driven double overhead camshafts (2xDOHC), and variable valve timing for both intake and exhaust valves. Engine management is by way of Bosch Motronic MED 9.1 electronic engine control unit (ECU), which controls the mapped direct ignition, ten individual spark coils, common rail cylinder-direct sequential mulit-point fuel injection, and drive by wire throttle.

The same engine is used in the latest Audi D3 S8, but in a higher state of tune where it develops 331 kilowatts (450 PS; 444 bhp). A ZF 6HP26 six-speed tiptronic automatic transmission (parts code: 09E, identification codes: JBW, JMS, KHD, JLL) (gear ratios - 1st: 4.171, 2nd: 2.340, 3rd: 1.521, 4th: 1.143, 5th: 0.867, 6th: 0.691), with steering wheel-mounted "paddle-shifters" is the only transmission available. Torsen-based quattro permanent four-wheel drive - initially with the T-2 symmetrical differential, and from 2007 model year with the latest 40:60 front:rear asymmetric/dynamic Torsen T-3 differential, are standard. The final drive ratio is 3.801. Traction is assisted "Electronic Differential Lock" (EDL) and "Anti-Slip Regulation" (ASR) (commonly known as traction control system) - both functions of the Bosch ESP 8.0 Electronic Stability Programme. For the sprint from rest to 100 kilometres per hour (62.1 mph), the S6 saloon takes 5.2 seconds, with the quarter mile passing in 13.5 seconds.[2] Top speed is electronically limited to 250 kilometres per hour (155.3 mph).

The brakes consist of radially ventilated discs front and rear. The fronts are sized at 385 millimetres (15.16 in) in diameter by 36 mm (1.417 in) thick, and are clamped by gloss black painted Continental Teves two-piston sliding calipers. The rear discs are 330 mm (12.99 in) by 22 millimetres (0.866 in) thick, and use gloss black Girling-TRW single piston sliding calipers with an integrated electro-mechanical parking brake. A Bosch ESP 8.0 Electronic Stability Programme, with Anti-lock Braking System (ABS), Brake Assist, and Electronic Brakeforce Distribution (EBD) completed the brake system. Standard alloy wheels consist of 9Jx19" cast aluminium alloy "5-arm wing design", shod with Continental SportContact2 265/35 ZR19 tyres. An optional 8½Jx18" cast alloy "S design" with 255/40 ZR18 tyres (either Conti SportContact2 or Bridgestone Potenza RE050A) are also available. A direct-acting Tyre Pressure Monitoring System (TPMS) is also standard.