RS 4 '01

The Audi RS4 quattro is the top tier and highest performing version of some specific generations of the Audi A4 range of automobiles. It is a sports-focused compact executive car (often called sport compact in some countries), produced by Audi's high-performance private subsidiary quattro GmbH, in limited numbers, for German car manufacturer AUDI AG, part of the larger Volkswagen Group. It slots distinctly above the Audi S4, as the fastest, most sports-focused model based on the A4's "B" automobile platform.

The original B5 version was only produced as a five-door five-seat "Avant", Audi's name for a estate car/station wagon. The second version, the B7, was released initially as a four-door five-seat saloon/sedan, with the Avant following a short while later. A two-door four-seat Cabriolet version was subsequently added. Furthermore, their unique internal combustion engines are all front-mounted, and are longitudinally oriented. The transmission is mounted immediately at the rear of the engine in a longitudinal orientation, in the form of a transaxle, and contains both a centre and front differential.

The "RS" initials are taken from the German: RennSport – literally translated as "racing sport", and is the Audi marque's highest trim level, positioned above the "S" model specification of Audi's regular model line-up. Like all Audi "RS" cars, the RS4 pioneers some of Audi's latest advanced technology, and could therefore be described as a "halo vehicle". Furthermore, it is only available with Audi's Torsen-based 'trademark' quattro permanent four-wheel drive system.

Its main market competitors initially included the BMW M3, and the Mercedes-Benz C63 AMG, and could also include the Lexus IS-F.

B5 (Typ 8D, 2000–2001)

Audi B5 RS4 Avant quattro
 
Production 2000–2001
Predecessor Audi RS2 Avant
Successor Audi B7 RS4
Body style(s) 5-door Avant (estate/wagon)
Platform Volkswagen Group B5
Engine(s) 2.7 L V6 'biturbo' 2xDOHC (ASJ/AZR)
Transmission(s) 6-speed manual
Wheelbase 2,607 mm (102.6 in)
Length 4,525 mm (178.1 in)
Width 1,799 mm (70.8 in)
Height 1,386 mm (54.6 in)
Curb weight 1,620 kg (3,571 lb)
Related Audi B5 A4
Audi B5 S4

The original B5 Audi RS4 Avant quattro (Typ 8D) was introduced by AUDI AG in late 1999, for main production and sale from 2000, as the successor to the Porsche / quattro GmbH joint venture-developed Audi RS2 Avant. The vehicle, like its RS2 predecessor, was available only as an Avant (Audi's name for an estate car/station wagon), and was built on an existing platform, in this case the Volkswagen Group B5 platform shared with the A4 and S4. Retail price was around Deutsche Mark 103,584. The RS4 was available for sale in most of Europe, parts of Asia and in some Latin American countries.

Audi produced 6,030 units between 1999 and 2001.

B5 bodywork and styling

Although related to the Audi B5 S4, many of the outer body panels are altered, with wider front and rear wheel arches, to allow for the wider axle track on the RS4. With unique front and rear bumpers, and side sills, and sharing the rear spoiler from the S4 Avant, the aerodynamic modifications achieved a drag coefficient of Cd 0.34. Although the B5 S4 came in a saloon car body style, the B5 RS4 was only available in the Avant version.

Luggage space, measured according to the industry standard VDA method is 390 liters (13.8 cu ft) with the rear seats in the upright position, and 1,250 litres (44.1 cu ft) with the seats folded flat.

B5 powertrain

For the powertrain detail of the B5 RS4, its motive power came from a modified version of the B5 S4's 2.7 litre V6 'biturbo' - a 2,671 cubic centimetres (163.0 cu in), 30 valve(five valves per cylinder) 90° V6 engine (parts code prefix: 078; identification codes: early version: 2000 ASJ, EU2 compliant, and later version: 2000-01 AZR, to EU3 standard). This engine was developed and manufactured in the UK by Cosworth Technology (now known as MAHLE Powertrain). It featured enlarged intake and smaller exhaust ports on the two Cosworth Cast Aluminum Alloy ALSi7mg cylinder heads, two parallel turbochargers (one per cylinder bank), larger side-mounted intercoolers (SMICs), dished pistons, stronger connecting rods, larger intake diameter hoses, enlarged exhaust system, and a re-calibrated engine management system. The modifications were enough to increase the engine's power output from the 195 kilowatts (265 PS; 261 bhp) and 400 newton metres (295 ft·lbf) of torque on the S4 to 280 kilowatts (381 PS; 375 bhp) at 7,000 revolutions per minute (rpm) and 440 newton metres (325 ft·lbf) at 6,000 rpm. Engine management is controlled via a Bosch Motronic ME 7.1 electronic engine control unit (ECU), utilising a Bosch 'E-Gas' electronic drive by wire throttle. Fuel is delivered via intake manifold-sited multipoint sequential indirect fuel injection, with fueling rate assisted by air mass metering. Ignition system uses six individual single-spark coils, utilising mapped direct ignition and NGK longlife spark plugs. This highly tuned engine must only be lubricated with a very high quality, low-viscosity, fully-synthetic oil (and must meet VW standard 503.01 or newer), as average oil temperatures can reach 135 °C (275 °F). Oil temperature is managed by a dual oil:water cooler, and an oil:air cooler.

A six-speed manual transmission (parts code prefix: 01E, identification code: FDP) (gear ratios - 1st: 3.500, 2nd: 1.889, 3rd: 1.320, 4th: 1.034, 5th: 0.806, 6th: 0.684), cooled by a NACA duct in the engine undertray, and Audi's Torsen-based quattro permanent four-wheel drive system, utilising the Torsen T-2 'automatic torque biasing' (ATB) center differential were standard. Final drive ratio is 4.111.

Even with a curb weight weight of 1,620 kilograms (3,571 lb), the RS4's powerful engine gave it the performance of a sports car. The 0 to 100 kilometres per hour (0 to 62.1 mph) dash could be reached in just 4.9 seconds, 160 kilometres per hour (99.4 mph) could be achieved in just 11.3 seconds, and 200 kilometres per hour (124.3 mph) could be reached in just 17.0 seconds. Top speed was electronically governed to 250 kilometres per hour (155.3 mph).

B5 brakes, wheels and tires

Brakes were also developed jointly in house by Audi's Quattro GmBH and Cosworth Technologies, not by Porsche as with its' predecessor, the RS2. It has 360 millimetres (14.2 in) diameter by 32 millimetres (1.26 in) thick radially vented and floating cast iron discs at the front, with double-piston floating brake calipers, and 312 millimetres (12.3 in) by 22 millimetres (0.87 in) discs with a single-piston floating caliper at the rear, giving the RS4 braking to match, needing less than 50 metres (160 ft) to come to a full stop from a speed of 110 kilometres per hour (68 mph).

Standard roadwheels are 18 inch alloys (8½ x18" "9-spoke"), with 255/35 ZR18 high performance tires. Optional "winter" alloy wheels were also available, at 18 inch (7½Jx18"), with 225/40 R18 92V tyres.

Other B5 notable features