The
Audi S4 is the
high performanceA sports sedan or a sports saloon is a descriptive term applied to a sedan automobile that is designed to look and feel "sporty", offering the motorist more connection with the driving experience, while providing the comfort and amenities expected of a luxury sedan. A wider definition that includes...
variant of
AudiAudi AG is a German automobile manufacturer, from supermini to crossover SUVs in various body styles and price ranges that are marketed under the Audi brand , positioned as the premium brand within the Volkswagen Group....
's
compact executive carCompact executive car is a car classification term applied to premium cars smaller than executive cars. In European classification, compact executive cars are part of the D-segment. In North American terms, close equivalents are compact premium car, compact luxury car, entry-level luxury car and...
A4. The original Audi S4, built from 1991 until 1994, was a performance-oriented version of Audi's
100The restyled C2 Audi 100 was launched in 1976, with an in-line five-cylinder engine...
saloon/sedan. All subsequent S4s since 1997 have been based on the
Audi A4The first generation Audi A4 debuted in 1994, with production starting November 1994. It was built on the Volkswagen Group B5 platform, which it shared with the fourth generation Volkswagen Passat . It had a front-mounted longitudinal engine and front-wheel drive...
; and as the A4 has evolved from one generation to the next, so has the S4.
A more powerful
internal combustion engineThe internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
, larger upgraded
brakeA brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....
s, firmer
suspensionSuspension is the term given to the system of springs, shock absorbers and linkages that connects a vehicle to its wheels. Suspension systems serve a dual purpose — contributing to the car's roadholding/handling and braking for good active safety and driving pleasure, and keeping vehicle occupants...
, larger
roadwheelsA wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...
, and distinctive sheetmetal, styling clues and badging have always been amongst the many upgrades the S4 receives over its mainstream 100 and A4 siblings. In markets where the even higher-performance
Audi RS4The 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 , produced by Audi's high-performance private subsidiary quattro GmbH, in limited numbers, for German car manufacturer...
is not offered, the S4 is the top-of-the-line trim of the A4 family.
Like its regular A4 counterpart, all S4 variants have had
longitudinally orientedIn automotive engineering, a longitudinal engine is an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, front to back....
,
front-mountedA front-mounted engine describes the placement of an automobile engine in front of the vehicle passenger compartment.Historically, this designation was used regardless of whether or not the entire engine was behind the front axle line...
engines. A single
turbochargedA turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
2.2 litre inline five-cylinder powered the original C4 version, and a 2.7 litre
'biturbo'Twin-turbo refers to a turbocharged engine, in which two turbochargers compress the intake charge. There are two commonly used twin turbo configurations: parallel twin-turbo and sequential twin-turbo...
V6 engineA V6 engine is a V engine with six cylinders mounted on the crankcase in two banks of three cylinders, usually set at either a right angle or an acute angle to each other, with all six pistons driving a common crankshaft...
was found in the B5 generation. The B6 and B7 versions shared a common 4.2 litre
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
, the first time that a V8 engine was placed in a compact executive car, placing it in direct competition with the BMW M3 which at the time had a 3.2 L inline 6. The recently introduced B8 generation uses a
superchargedA supercharger is an air compressor used for forced induction of an internal combustion engine.The greater mass flow-rate provides more oxygen to support combustion than would be available in a naturally aspirated engine, which allows more fuel to be burned and more work to be done per cycle,...
3.0 litre V6 TFSI engine and competes with the BMW 335i.
All versions of the S4 have their
transmissionA machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...
mounted immediately at the rear of the engine in a longitudinal orientation, in the form of a
transaxleIn the automotive field, a transaxle is a major mechanical component that combines the functionality of the transmission, the differential, and associated components of the driven axle into one integrated assembly....
, and like all Audi "S" cars, are only available as standard with Audi's quattro
four-wheel driveFour-wheel drive, 4WD, or 4×4 is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously...
(4WD) system, using a
TorsenTorsen is a type of differential used in automobiles. It was invented by American Vernon Gleasman and manufactured by the Gleason Corporation. Torsen is a contraction of Torque-Sensing...
-based centre diff system.
All versions of the S4 have been
manufacturedModern automotive engineering, along with aerospace engineering and marine engineering, is a branch of vehicle engineering, incorporating elements of mechanical, electrical, electronic, software and safety engineering as applied to the design, manufacture and operation of motorcycles, automobiles,...
at Audi's plant in
IngolstadtIngolstadt is a city in the Free State of Bavaria, in the Federal Republic of Germany. It is located along the banks of the Danube River, in the center of Bavaria. As at 31 March 2011, Ingolstadt had 125.407 residents...
,
GermanyGermany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
; they are, or have been available as a four-
doorA vehicle door is a partition, typically hinged, but sometimes attached by other mechanisms such as tracks, in front of an opening which is used for entering and exiting a vehicle. A vehicle door can be opened to provide access to the opening, or closed to secure it. These doors are similar to...
five-seat saloon and a five-door five-seat Avant (Audi's name for an
estate car/station wagonA station wagon is a body style variant of a sedan/saloon with its roof extended rearward over a shared passenger/cargo volume with access at the back via a third or fifth door , instead of a trunk lid...
)
body stylesAutomobiles' body styles are highly variable. Some body styles remain in production, while others become less common or obsolete. They may or may not correlate to a car's price, size or intended market classification. The same car model might be available in multiple body styles comprising a...
since the model's inception in 1991. A two-door four-seat Cabriolet (
convertibleA convertible is a type of automobile in which the roof can retract and fold away having windows which wind-down inside the doors, converting it from an enclosed to an open-air vehicle...
) S4 variant was introduced as part of the B6 and B7 generation A4 lineups. The B8 Cabriolet has now been built off the A5 coupe body style and the "S" variant is marketed under the Audi S5 nameplate.
C4 (Typ 4A, 1991–1994)
Factory production of the original Audi S4 (Typ 4A) began in August 1991 to serve as the performance version of the newly updated C4 platform 100 four-
doorA vehicle door is a partition, typically hinged, but sometimes attached by other mechanisms such as tracks, in front of an opening which is used for entering and exiting a vehicle. A vehicle door can be opened to provide access to the opening, or closed to secure it. These doors are similar to...
, five-seat saloon. It was designed to replace the outgoing C3 based Audi 200 quattro turbo, which had been Audi's first true sports-saloon and had been discontinued at the end of 1990. Being the first S4 model from Audi, it is commonly referred to as the , derrived from the augmentive word (meaning: original).
Audi mildly updated the C4-based model line in 1994 and dropped the 100 nomenclature; all variants of the former Audi 100 line were now
re-badgedBadge engineering is an ironic term that describes the rebadging of one product as another...
as the
Audi A6The Audi A6 is an executive car marketed by the German automaker Audi AG, now in its fourth generation. As the successor to the Audi 100, the A6 is manufactured in Neckarsulm, Germany – and is available in saloon, and wagon configurations, the latter marketed by Audi as the Avant.All generations...
. In line with the switch in model name, Audi temporarily discontinued the use of the S4 name and began selling an updated but fundamentally identical version of the car, based on the "new" A6 and badged as
S6The 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...
. Despite the change in name, differences between the outgoing S4 and incoming S6 were primarily cosmetic.
A more powerful, more expensive and more exclusive variant known first as the S4 Plus
and later as the S6 Plus was available from October 1992 through to July 1994. Built in very small numbers, the "Plus" models featured numerous performance enhancing upgrades; including the use of Audi's 4.2 litre
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
in place of the then current inline-five engine.
An all-new C5-based Audi A6 debuted for 1997, after which the S4 and S6 became distinctly separate models based on very different platforms.
The C4 variant S4 ended factory production after less than three years in July 1994.
C4 powertrain
In standard form, the
powertrainIn a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...
detail of the C4-based S4 was available with only one engine, a single
turbochargedA turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
and
intercooledAn intercooler , or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged and supercharged internal combustion engines to improve their volumetric efficiency by increasing intake air charge density through nearly isobaric cooling, which removes...
version of Audis 2.2 litre
20-valveIn automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and can operate at higher revolutions per minute than a two-valve engine, delivering more power.- Multi-valve rationale :A multi-valve design...
inline five cylinder engine This displaced 2226 cc and was equipped with an advanced
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
MotronicMotronic is the trade name given to a range of digital engine-management systems developed by Robert Bosch GmbH, commonly known as Bosch.-Motronic ML1.x:Motronic ML1.x was one of the first digital engine-management systems developed by Bosch...
electronic
engine control unitAn engine control unit is a type of electronic control unit that determines the amount of fuel, ignition timing and other parameters an internal combustion engine needs to keep running...
(ECU). This engine (parts code prefix: 034, identification code: AAN), developed a
motiveIn thermodynamics, motive power is an agency, as water or steam, used to impart motion. Generally, motive power is defined as a natural agent, as water, steam, wind, electricity, etc., used to impart motion to machinery; a motor; a mover. The term may also define something, as a locomotive or a...
powerIn physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output of 169 kW at 5,900
revolutions per minuteRevolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
(rpm) and 350 newton metres (258 ft·lbf) of
torqueTorque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
1,950 rpm. This powerplant made it rather powerful by contemporary standards, and the vehicle with five-speed manual transmission was able to accelerate from standstill to 100 kilometres per hour (62.1 mph) in just 6.2 seconds.
Both five- and six-speed
manual transmissionA manual transmission, also known as a manual gearbox or standard transmission is a type of transmission used in motor vehicle applications...
s (parts code prefix: 01E, identification codes: five-speed: CBD, CET, six-speed: CBL, CMG) were offered to
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an customers, but a five-speed manual was the only transmission available in
North AmericaNorth America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
; a four-speed
automatic transmissionAn automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...
(parts code prefix: 01F, identification code: CBF) was available as an option worldwide. Front and rear
axleAn axle is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to its surroundings, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle...
final drive
ratioThe gear ratio of a gear train is the ratio of the angular velocity of the input gear to the angular velocity of the output gear, also known as the speed ratio of the gear train. The gear ratio can be computed directly from the numbers of teeth of the various gears that engage to form the gear...
is either 4.111 or 3.889 (dependent on transmission type), and the rear axle (parts code prefix: 017, identification codes: AAT, AET) uses a driver-selectable electro-pneumatic-mechanical switchable
diff lockA locking differential, diff-lock or locker is a variation on the standard automotive differential. A locking differential may provide increased traction compared to a standard, or "open" differential by restricting each of the two wheels on an axle to the same rotational speed without regard to...
.
Audi's quattro four-wheel-drive system was standard on the C4 S4/S6; a first-generation
TorsenTorsen is a type of differential used in automobiles. It was invented by American Vernon Gleasman and manufactured by the Gleason Corporation. Torsen is a contraction of Torque-Sensing...
-based system which used the "T-1" automatically biasing centre differential (ATB) was used on vehicles equipped with manual transmissions, while a
transfer boxA transfer case is a part of a four-wheel-drive system found in four-wheel-drive and all-wheel-drive vehicles. The transfer case is connected to the transmission and also to the front and rear axles by means of drive shafts...
based system was used on vehicles equipped with an
automatic transmissionAn automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...
.
S4/S6 "Plus" models equipped with a 4.2 litre 206 kW all-
aluminium alloyAluminium alloys are alloys in which aluminium is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories...
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
(parts code prefix: 077, identification code: ABH) became available to
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an customers as an option from October 1992, only with the six-speed manual gearbox, in either saloon or Avant bodystyles.
C4 steering, brakes, wheels & tyres
All C4 S4s' came equipped as standard with a conventional fixed-assistance rack and pinion
power assisted steeringPower steering helps drivers steer vehicles by augmenting steering effort of the steering wheel.Hydraulic or electric actuators add controlled energy to the steering mechanism, so the driver needs to provide only modest effort regardless of conditions. Power steering helps considerably when a...
(PAS) system. An electronically controlled 'servotronic' system, which varied the level of assistance in accordance with the road speed, was available as an option.
There were two different types of high performance brake systems on offer for the C4 S4. All S4s' initially had 310 millimetres (12.2 in) diameter by 25 millimetre (0.984251968503937 in) thick, radially ventilated
disc brakeThe disc brake or disk brake is a device for slowing or stopping the rotation of a wheel while it is in motion.A brake disc is usually made of cast iron, but may in some cases be made of composites such as reinforced carbon–carbon or ceramic matrix composites. This is connected to the wheel and/or...
s up front, each with an
ATEContinental AG, internally often called Conti for short, is a worldwide leading German manufacturer of tires, brake systems, vehicle stability control systems, engine injection systems, tachographs and other parts for the automotive and transport industries. The company is based in Hanover, Germany...
single-piston sliding caliper inside a 'UFO' styled bell-shaped disc. With the introduction of the V8 engine, a new front brake setup became standard; again the discs used radial ventilation, but these front discs were now sized at 314 millimetres (12.36 in) by 30 millimetres (1.181 in) - with a conventionally mounted
LucasLucasVarity plc was a UK automotive parts manufacturer, created by a merger of the British Lucas Industries plc, and the North American Varity Corporation in August 1996.-Foundation:...
-Girling caliper in an external position over the disc. US models had smaller 276 millimetres (10.87 in) discs. The rear brakes, 269 millimetres (10.59 in) by 20 millimetre (0.78740157480315 in) and also radially ventilated - remained the same throughout C4 production; they used a Lucas-Girling single-piston sliding caliper with an integrated cable-actuated handbrake mechanism. A
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
three-channel operation (four-channel sensing)
Anti-lock Braking SystemAn anti-lock braking system is a safety system that allows the wheels on a motor vehicle to continue interacting tractively with the road surface as directed by driver steering inputs while braking, preventing the wheels from locking up and therefore avoiding skidding.An ABS generally offers...
(ABS) with a mechanical load sensing valve for the rear brakes was standard throughout production.
For
roadwheelA wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...
options, the standard five-arm "fuch" forged
alloy wheelAlloy wheels are automobile wheels which are made from an alloy of aluminium or magnesium. They are typically lighter for the same strength...
s were 8.0Jx16H2 ET40, and were shod with 225/50 R16
sizedAutomobile tires are described by an alphanumeric tire code or tyre code , which is generally molded into the sidewall of the tire. This code specifies the dimensions of the tire, and some of its key limitations, such as load-bearing ability, and maximum speed...
tyres. Three other
tyreA tire or tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground...
and roadwheel designs were optionally available: a 7.5Jx15H2 ET40 six-spoke with 215/60 R15 tyres, a 8.0Jx16H2 ET40 five-double-spoke, and a 8.0Jx17H2 ET40 ten-spoke.
B5 (Typ 8D, 1997–2002)
The second generation S4 (Typ 8D), now correctly titled
Audi S4 quattro debuted in 1997, with factory production commencing October 1997, as part of the facelifted B5 platform Audi A4 line-up, although it wasn't available in
North AmericaNorth America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
until late 1999.
In addition to the saloon (sedan), an
estateA station wagon is a body style variant of a sedan/saloon with its roof extended rearward over a shared passenger/cargo volume with access at the back via a third or fifth door , instead of a trunk lid...
version (wagon)–the Audi S4 Avant–was introduced into the lineup from 1998. Production of the B5 S4 ceased in September 2001, although it was still sold together with the next B6 platform generation through 2002 in North America. Examples produced July 2001 to end of production are 2002 Model Year cars, the 10th digit of the VIN being the number "2".
Several years after it was sold new, the B5 S4 remains a potent enthusiast car, and as featured in the December 2007 issue of
Sport Compact Car magazine, a Torque Factory tuned S4 won a comparison test against several other extreme performance cars.
B5 powertrain
The
powertrainIn a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...
detail of the B5 S4 features a 2.7 litre
twin-turboTwin-turbo refers to a turbocharged engine, in which two turbochargers compress the intake charge. There are two commonly used twin turbo configurations: parallel twin-turbo and sequential twin-turbo...
('biturbo') 90° third-generation
V6 engineA V6 engine is a V engine with six cylinders mounted on the crankcase in two banks of three cylinders, usually set at either a right angle or an acute angle to each other, with all six pistons driving a common crankshaft...
(parts code prefix: 078, identification codes: AGB, AZB). Detail of the powerplant includes a
cast ironCast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...
cylinder blockA cylinder block is an integrated structure comprising the cylinder of a reciprocating engine and often some or all of their associated surrounding structures...
with two lightweight
aluminium alloyAluminium alloys are alloys in which aluminium is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories...
cylinder headIn an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket...
s. The
valvetrainValvetrain is an all-encompassing term used to describe the mechanisms and parts which control the operation of the valves. A traditional reciprocating internal combustion engine uses valves to control air and fuel flow into and out of the cylinders, facilitating combustion.-Layout:Valvetrain: The...
includes
30 valvesIn automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and can operate at higher revolutions per minute than a two-valve engine, delivering more power.- Multi-valve rationale :A multi-valve design...
(five valves per
cylinderA cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...
), twin hybrid-driven (
timing beltA timing belt, or cam belt , is a part of an internal combustion engine that controls the timing of the engine's valves. Some engines, such as the flat-4 Volkswagen air-cooled engine, and the straight-6 Toyota F engine use timing gears...
and
roller chainRoller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire and tube drawing machines, printing presses, cars, motorcycles, and simple machines like...
) double overhead camshafts and
variable valve timingIn internal combustion engines, variable valve timing , also known as Variable valve actuation , is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine...
for the inlet valves. The charged intake air is cooled with the aid of two side-mounted
intercoolerAn intercooler , or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged and supercharged internal combustion engines to improve their volumetric efficiency by increasing intake air charge density through nearly isobaric cooling, which removes...
s (SMICs). It
displacesEngine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...
2671 cc, and is rated to produce a
motiveIn thermodynamics, motive power is an agency, as water or steam, used to impart motion. Generally, motive power is defined as a natural agent, as water, steam, wind, electricity, etc., used to impart motion to machinery; a motor; a mover. The term may also define something, as a locomotive or a...
powerIn physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output of 195 kW at 5,800
revolutions per minuteRevolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
(rpm), and generates 400 newton metres (295 ft·lbf) of
torqueTorque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
at 1,850 rpm. Engine management was by way of a
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
MotronicMotronic is the trade name given to a range of digital engine-management systems developed by Robert Bosch GmbH, commonly known as Bosch.-Motronic ML1.x:Motronic ML1.x was one of the first digital engine-management systems developed by Bosch...
ME 7.1 (7.0 in North America) electronic
engine control unitAn engine control unit is a type of electronic control unit that determines the amount of fuel, ignition timing and other parameters an internal combustion engine needs to keep running...
(ECU), and helped it meet the European EU-3D emissions standard. For a short
time scaleA time scale specifies divisions of time.*Time standard, a specification of either the rate at which time passes, or points in time, or both*Duration , a quantity of time...
(08/98-12/98) in the North American market, the engine was slightly detuned to meet US emissions regulations, output was reduced to 187 kW and 350 newton metres (258 ft·lbf) (identification code: APB).
As in the previous S4, a six-speed C90
manual transmissionA manual transmission, also known as a manual gearbox or standard transmission is a type of transmission used in motor vehicle applications...
(parts code prefix: 01E, identification code: DSY,
gear ratioThe gear ratio of a gear train is the ratio of the angular velocity of the input gear to the angular velocity of the output gear, also known as the speed ratio of the gear train. The gear ratio can be computed directly from the numbers of teeth of the various gears that engage to form the gear...
s: 1st: 3.500, 2nd: 1.889, 3rd: 1.231, 4th: 0.967, 5th: 0.806, 6th: 0.684) was standard equipment, as was the Torsen T-2 quattro permanent
four-wheel driveFour-wheel drive, 4WD, or 4×4 is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously...
system. Final drive (parts code prefix: 01H, identification code: DQA) ratio is 4.111. A five-speed
ZFZF Friedrichshafen AG, also known as ZF Group, and commonly abbreviated to ZF, is a German public company headquartered in Friedrichshafen, in the south-west German region of Baden-Württemberg....
5HP19 tiptronic
automatic transmissionAn automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...
(parts code prefix:01V) became available for the first time as an option.
The B5 S4 claims acceleration from 0 to 100 km/h (0 to 62.1 ) in 5.6 seconds, and had an electronically-limited top speed of 250 km/h (155.3 mph), making it both the quickest saloon/sedan in the Audi model line, and among the quickest saloon/sedans in the world at that time.
B5 brakes, wheels & tires
The B5 S4
brakeA brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....
system consisted of radially ventilated discs, 321 millimetres (12.64 in) in diameter by 30 mm (1.18 in) thick up front, and 256 mm (10.08 in) by 22 mm (0.866141732283465 in) at the rear. Two-piston
LucasLucasVarity plc was a UK automotive parts manufacturer, created by a merger of the British Lucas Industries plc, and the North American Varity Corporation in August 1996.-Foundation:...
HP2 brake calipers at the front (with four pads per caliper), with Lucas single-piston sliding brake calipers at the rear. A
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
ABS 5.3 four-channel
Anti-lock Braking SystemAn anti-lock braking system is a safety system that allows the wheels on a motor vehicle to continue interacting tractively with the road surface as directed by driver steering inputs while braking, preventing the wheels from locking up and therefore avoiding skidding.An ABS generally offers...
(with
Electronic Brakeforce DistributionElectronic brakeforce distribution ', Electronic brakeforce limitation ' is an automobile brake technology that automatically varies the amount of force applied to each of a vehicle's brakes, based on road conditions, speed, loading, etc...
(EBD) and Electronic Differential Lock (EDL) - and later with ESP or
Electronic Stability ProgrammeElectronic stability control is a computerized technology that may potentially improve the safety of a vehicle's stability by detecting and minimizing skids. When ESC detects loss of steering control, it automatically applies the brakes to help "steer" the vehicle where the driver intends to go...
), coupled with a
vacuum servoA vacuum servo is a component used on motor vehicles in their braking system, to provide assistance to the driver by decreasing the braking effort. In the USA it is commonly called a brake booster.-Background:...
completed the system.
Standard
roadwheelsA wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...
were Audi's
die-castDie casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mold cavity. The mold cavity is created using two hardened tool steel dies which have been machined into shape and work similarly to an injection mold during the process...
aluminium alloyAluminium alloys are alloys in which aluminium is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories...
six-arm 'Avus' 7.5Jx17H2 ET45
alloy wheelAlloy wheels are automobile wheels which are made from an alloy of aluminium or magnesium. They are typically lighter for the same strength...
s, shod with 225/45 ZR17 performance
tyresA tire or tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground...
.
B5 colors & optional equipment
Available exterior colors included Brilliant Black, Laser Red, Light Silver, Cactus Green, Santorin Blue, Hibiscus Red, Casablanca White, Imola Yellow, and Nogaro Blue. The last two colors were exclusive to the S4 model. Interior leather was available in Oynx or Silver. Available options included:
- Bose premium sound system
- Audi Navigation System
- 6-disc CD changer
- Hands free Motorola cellular telephone
- Premium Package: Sunroof, HomeLink transmitter, Auto dimming mirrors
- Cold Weather Package: Heated front seats, Heated outside mirrors, Expandable ski sack
- Enhanced Sport Package: Alcantara seat inserts, Silver aluminum belt line trim, Aluminum mirror housings (on 2001 & 2002 models)
The Sport Package replaced the wood-grain belt line trim with sliver aluminum trim, and the wood grain finish around the shifter with black plastic. The Alcantara seat inserts were silver (on Oynx leather). With the black, white, or blue exteriors, the inserts were also available in blue Alcantara. On the early 2000 models, the Alcantara inserts in the rear seats did not fuly extend forward to the front edge of the seat.
B5 motorsport
A
motor racingAuto racing is a motorsport involving the racing of cars for competition. It is one of the world's most watched televised sports.-The beginning of racing:...
version of the car achieved great success in the
SpeedVision World ChallengeThe Pirelli World Challenge is a North American auto racing series that is sanctioned by the Sports Car Club of America . Founded in 1985, it consists of four classes: grand touring, touring car, a "GTS" class since 2010, and a "touring car B-spec" since 2012...
with Michael Galati taking the 2001 SpeedVision GT title in a
Champion RacingChampion Racing is a sports car racing team based in Pompano Beach, Florida, USA. Founded in 1994 by Dave Maraj as the motorsport wing of the Champion Motors car dealership, the team has campaigned various Porsches and Audis in North American road racing series...
S4, winning four races, and helping Audi to its first Manufacturers' Championship.
The Audi Sport specification Champion A4 chassis included a B5 RS4 engine, and Alcon racing brake calipers - 4-pot fronts and 2-pot rears.
B6 (Typ 8E/8H, 2003–2005)
The third generation
Audi S4 quattro (Typ 8E — saloon: 8E2, Avant: 8E5, and Cabriolet: 8H7) debuted its saloon and Avant
bodystylesAutomobiles' body styles are highly variable. Some body styles remain in production, while others become less common or obsolete. They may or may not correlate to a car's price, size or intended market classification. The same car model might be available in multiple body styles comprising a...
in
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
in March 2003, and appeared in
North AmericaNorth America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
slightly later. This was based on the latest Volkswagen Group B6 (PL46) platform used by the then current Audi B6 A4. Despite having moved to an entirely new platform, one of the S4's most publicised new features was its new
internal combustion engineThe internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
- a 4.2 litre
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
. Following its initial launch of either a four-
doorA vehicle door is a partition, typically hinged, but sometimes attached by other mechanisms such as tracks, in front of an opening which is used for entering and exiting a vehicle. A vehicle door can be opened to provide access to the opening, or closed to secure it. These doors are similar to...
five-
seatA car seat is the chair used in automobiles. Most car seats are made from inexpensive but durable material in order to withstand as much use as possible.-Ergonomy: Lumbar and thigh support:...
saloon (sedan), or a five-door five-seat Avant (estate/wagon), it eventually became available in three bodystyles - and for the first time in the Audi 'S' car range, from February 2004, a two-door four-seat Cabriolet (
convertibleA convertible is a type of automobile in which the roof can retract and fold away having windows which wind-down inside the doors, converting it from an enclosed to an open-air vehicle...
), Typ 8H, was included in the model range.
Official performance figures for standard discipline of sprinting from standstill to 100 kilometres per hour (62.1 mph) in the saloon with manual transmission are 5.6 seconds (Avant 5.8 s, Cabriolet 5.9 s), however, a road test conducted by the American automotive magazine
Motor TrendMotor Trend is an American automobile magazine. It first appeared in September 1949, issued by Petersen Publishing Company in Los Angeles, and bearing the tag line "The Magazine for a Motoring World". Petersen Publishing was sold to British publisher EMAP in 1998, who sold the former Petersen...
indicated that it could go from a standstill to 60 mph (26.8 m/s) in less than 5 seconds, and make it to 200 km/h (124.3 mph) in slightly over 20 seconds, although doing this led to fuel consumption dipping into single digits, considerably lower than the earlier V6 models, leading to the addition of a $1,700
gas guzzler taxThe National Energy Act: Energy Tax Act of 1978 , or the Gas Guzzler Tax, imposed set tax penalties on car manufacturers who fail to meet the minimum fuel economy level of in the United States. This does not include minivans, sport utility vehicles or pick-up trucks. It is intended to discourage...
(combined 20.2 miles per US gallon) for the six-speed manual sedan in the
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Top speed is electronically limited to 250 km/h (155.3 mph).
The B6 S4 saloon and Avant variants ceased factory production in December 2004, with the Cabriolet ending twelve months later at December 2005.
B6 powertrain
Replacing the 2.7 litre '
biturboTwin-turbo refers to a turbocharged engine, in which two turbochargers compress the intake charge. There are two commonly used twin turbo configurations: parallel twin-turbo and sequential twin-turbo...
'
V6 engineA V6 engine is a V engine with six cylinders mounted on the crankcase in two banks of three cylinders, usually set at either a right angle or an acute angle to each other, with all six pistons driving a common crankshaft...
of the previous generation B5 S4, the new B6 S4
powertrainIn a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...
gained an all-
aluminium alloyAluminium alloys are alloys in which aluminium is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories...
4.2 litre,
40 valveIn automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and can operate at higher revolutions per minute than a two-valve engine, delivering more power.- Multi-valve rationale :A multi-valve design...
(five valves per
cylinderA cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...
)
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
(parts code prefix: 079.C, identification code: BBK), with twin
chainA chain is a sequence of connected links.Chain may also refer to:Chain may refer to:* Necklace - a jewelry which is worn around the neck* Mail , a type of armor made of interlocking chain links...
-driven (at the rear of the
engineThe internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
) two double overhead camshafts (2xDOHC) (two per
cylinder bankInternal combustion piston engines are usually arranged so that the cylinders are in lines parallel to the crankshaft. Where they are in a single line, this is referred to as an inline or straight engine....
- 'quad cam'), roller-finger
rocker armGenerally referred to within the internal combustion engine of automotive, marine, motorcycle and reciprocating aviation engines, the rocker arm is a reciprocating lever that conveys radial movement from the cam lobe into linear movement at the poppet valve to open it...
cam followerA cam follower, also known as a track follower, is a specialized type of roller or needle bearing designed to follow cams. Cam followers come in a vast array of different configurations, however the most defining characteristic is how the cam follower mounts to its mating part; stud style cam...
s, and included
variable inlet camshaft timingIn internal combustion engines, variable valve timing , also known as Variable valve actuation , is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine...
. It also utilised a strengthened alloy
crankshaftThe crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...
bedplate for the five
main bearingIn a piston engine, the main bearings are the bearings on which the crankshaft rotates, usually plain or journal bearings.All engines have a minimum of two main bearings, one at each end of the crankshaft, and they may have as many as one more than the number of crank pins...
s, and a two-part
baffleBaffle or baffles may refer to:* Baffle , a flow-directing vane or panel in some vessels such as shell and tube heat exchangers, chemical reactors, or static mixers...
d oil
sumpA sump is a low space that collects any often-undesirable liquids such as water or chemicals. A sump can also be an infiltration basin used to manage surface runoff water and recharge underground aquifers....
, and a light-alloy
variable intake manifoldIn internal combustion engines, a variable length intake manifold , or variable intake manifold is an automobile internal combustion engine manifold technology...
(VIM), containing the sequentially actuated
fuel injectorsFuel injection is a system for admitting fuel into an internal combustion engine. It has become the primary fuel delivery system used in automotive petrol engines, having almost completely replaced carburetors in the late 1980s....
. This
petrol engineA petrol engine is an internal combustion engine with spark-ignition, designed to run on petrol and similar volatile fuels....
, based on the unit from the
Audi A8The Audi A8 is a four-door, full-size, luxury sedan car manufactured and marketed by the German automaker Audi since 1994. Succeeding the Audi V8, the A8 has been offered with front wheel drive or permanent four-wheel drive, with multitronic or tiptronic automatic transmissions — and in short- and...
,
displacesEngine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...
4163 cc, and it produces a
motiveIn thermodynamics, motive power is an agency, as water or steam, used to impart motion. Generally, motive power is defined as a natural agent, as water, steam, wind, electricity, etc., used to impart motion to machinery; a motor; a mover. The term may also define something, as a locomotive or a...
powerIn physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output of 253 kW at 7,000
revolutions per minuteRevolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
(rpm), and generates
torqueTorque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
of 410 newton metres (302 ft·lbf) at 3,500 rpm, making it more potent than the
RS2 AvantThe Audi RS2 Avant was a limited edition, high-performance Audi five-door, five-seat estate car , manufactured from March 1994 to July 1995...
, and nearly as powerful as the B5 RS4. Engine management was by way of a
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
MotronicMotronic is the trade name given to a range of digital engine-management systems developed by Robert Bosch GmbH, commonly known as Bosch.-Motronic ML1.x:Motronic ML1.x was one of the first digital engine-management systems developed by Bosch...
ME 7.1.1 electronic
engine control unitAn engine control unit is a type of electronic control unit that determines the amount of fuel, ignition timing and other parameters an internal combustion engine needs to keep running...
(ECU), utilising a Bosch 'E-Gas'
drive by wireDrive-by-wire, DbW, by-wire, or x-by-wire technology in the automotive industry replaces the traditional mechanical control systems with electronic control systems using electromechanical actuators and human-machine interfaces such as pedal and steering feel emulators...
electronic throttle, and powering eight individual
spark coilsAn ignition coil is an induction coil in an automobile's ignition system which transforms the battery's 12 volts to the thousands of volts needed to create an electric spark in the spark plugs to ignite the fuel...
with longlife quad-electrode Bosch
spark plugA spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed fuels such as aerosol, gasoline, ethanol, and liquefied petroleum gas by means of an electric spark.Spark plugs have an insulated central electrode which is connected by...
s.
Ignition timingIgnition timing, in a spark ignition internal combustion engine , is the process of setting the angle relative to piston position and crankshaft angular velocity that a spark will occur in the combustion chamber near the end of the compression stroke...
is a mapped direct
ignitionAn ignition system is a system for igniting a fuel-air mixture. Ignition systems are well known in the field of internal combustion engines such as those used in petrol engines used to power the majority of motor vehicles, but they are also used in many other applications such as in oil-fired and...
, with cylinder-selective knock control with the aid of four knock sensors. The
exhaust systemAn exhaust system is usually tubing used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove. The entire system conveys burnt gases from the engine and includes one or more exhaust pipes...
includes
vacuumIn everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
-operated valves in the twin rear
silencersA muffler is a device for reducing the amount of noise emitted by the exhaust of an internal combustion engine. A US Patent for an Exhaust muffler for engines was granted to Milton and Marshall Reeves in 1897....
(mufflers), finished with
chrome platedChrome plating, often referred to simply as chrome, is a technique of electroplating a thin layer of chromium onto a metal object. The chromed layer can be decorative, provide corrosion resistance, ease cleaning procedures, or increase surface hardness.-Process:A component to be chrome plated will...
tail-pipes.
Like its predecessors, the B6 S4 was standard with a
GetragGetrag is a leading manufacturer of automobile manual transmissions. The company was founded on 1 May 1935, in Ludwigsburg, Germany, by Hermann Hagenmeyer; as the Getriebe und Zahnradfabrik Hermann Hagenmeyer GmbH & Cie KG...
six-speed (M6S) manual transmission (parts code prefix: 0A3, identification codes: FVD, HEP) (
gear ratioThe gear ratio of a gear train is the ratio of the angular velocity of the input gear to the angular velocity of the output gear, also known as the speed ratio of the gear train. The gear ratio can be computed directly from the numbers of teeth of the various gears that engage to form the gear...
s - 1st: 3.667, 2nd: 2.050, 3rd: 1.462, 4th: 1.133, 5th: 0.919, 6th: 0.778), with a 240 millimetre single plate dry
clutchA clutch is a mechanical device which provides for the transmission of power from one component to another...
, and
TorsenTorsen is a type of differential used in automobiles. It was invented by American Vernon Gleasman and manufactured by the Gleason Corporation. Torsen is a contraction of Torque-Sensing...
T-2 quattro permanent
four-wheel driveFour-wheel drive, 4WD, or 4×4 is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously...
system. Final drive (parts code prefix: 01R, identification code: EXZ) ratios are 3.889, giving a top gear road speed to engine revs ratio of 24.4 miles per hour (10.9 m/s) per 1000 rpm. From July 2003, the
ZFZF Friedrichshafen AG, also known as ZF Group, and commonly abbreviated to ZF, is a German public company headquartered in Friedrichshafen, in the south-west German region of Baden-Württemberg....
6HP19The ZF 6HP19 transmission is the second generation automatic transmission for passenger cars of the 6HP series manufactured by ZF Friedrichshafen AG. It retains many of the features found in the ZF 6HP26 transmission.Gear ratios:-6HP19A:...
tiptronic
automatic transmissionAn automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...
(parts code prefix: 09L, identification codes: GUR, HHU) (ratios - 1st: 4.171, 2nd: 2.340, 3rd: 1.521, 4th: 1.143, 5th: 0.867, 6th: 0.691, with a final drive (identification code: GDF) ratio of 3.539) was included as an option.
An unusual sight in the engine compartment was the addition of water cooling for the 190
ampThe ampere , often shortened to amp, is the SI unit of electric current and is one of the seven SI base units. It is named after André-Marie Ampère , French mathematician and physicist, considered the father of electrodynamics...
alternator, along with two additional
thermostatA thermostat is the component of a control system which regulates the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature. The thermostat does this by switching heating or cooling devices on or off, or regulating the flow of a heat transfer...
ically-controlled side-mounted
radiatorsRadiators are used for cooling internal combustion engines, mainly in automobiles but also in piston-engined aircraft, railway locomotives, motorcycles, stationary generating plant or any similar use of such an engine....
.
B6 steering, brakes, wheels & tyres
The B6 S4 came equipped with electronically controlled, variable assisted 'servotronic' rack and pinion
power assisted steeringPower steering helps drivers steer vehicles by augmenting steering effort of the steering wheel.Hydraulic or electric actuators add controlled energy to the steering mechanism, so the driver needs to provide only modest effort regardless of conditions. Power steering helps considerably when a...
(PAS) as standard.
B6 S4
brakeA brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....
s consisted of radially ventilated
disc brakeThe disc brake or disk brake is a device for slowing or stopping the rotation of a wheel while it is in motion.A brake disc is usually made of cast iron, but may in some cases be made of composites such as reinforced carbon–carbon or ceramic matrix composites. This is connected to the wheel and/or...
s front and rear. The front discs are sized at 345 millimetres (13.58 in) in diameter by 30 mm (1.181 in) thick, and are clamped by
Continental Teves-ATEContinental AG, internally often called Conti for short, is a worldwide leading German manufacturer of tires, brake systems, vehicle stability control systems, engine injection systems, tachographs and other parts for the automotive and transport industries. The company is based in Hanover, Germany...
FNRG-60 single-piston sliding brake calipers. The rears are 300 mm (11.81 in) by 22 mm (0.866141732283465 in), and again use single-piston sliding calipers, with an integrated cable-operated
hand brakeIn cars, the hand brake is a latching brake usually used to keep the car stationary, and in manual transmission vehicles, as an aid to starting the vehicle from stopped when going up an incline - with one foot on the clutch , the other on the accelerator In cars, the hand brake (emergency brake,...
mechanism. A
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
ESP 5.7
Electronic Stability ProgrammeElectronic stability control is a computerized technology that may potentially improve the safety of a vehicle's stability by detecting and minimizing skids. When ESC detects loss of steering control, it automatically applies the brakes to help "steer" the vehicle where the driver intends to go...
system, complete with
Anti-lock Braking SystemAn anti-lock braking system is a safety system that allows the wheels on a motor vehicle to continue interacting tractively with the road surface as directed by driver steering inputs while braking, preventing the wheels from locking up and therefore avoiding skidding.An ABS generally offers...
(ABS),
Electronic Brakeforce DistributionElectronic brakeforce distribution ', Electronic brakeforce limitation ' is an automobile brake technology that automatically varies the amount of force applied to each of a vehicle's brakes, based on road conditions, speed, loading, etc...
(EBD),
Emergency Brake AssistEmergency Brake Assist is a safety system in motor vehicles designed to ensure maximum braking power is used in an emergency stop situation...
(EBA), Electronic Differential Lock (EDL) and Anti-Slip Regulation (ASR) - also known as
traction control systemA traction control system , also known as anti-slip regulation , is typically a secondary function of the anti-lock braking system on production motor vehicles, designed to prevent loss of traction of driven road wheels...
, coupled with a dual-rate tandem
vacuum servoA vacuum servo is a component used on motor vehicles in their braking system, to provide assistance to the driver by decreasing the braking effort. In the USA it is commonly called a brake booster.-Background:...
provided the brake actuation.
Standard
alloy wheelAlloy wheels are automobile wheels which are made from an alloy of aluminium or magnesium. They are typically lighter for the same strength...
s were 'Avus-III'
die-castDie casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mold cavity. The mold cavity is created using two hardened tool steel dies which have been machined into shape and work similarly to an injection mold during the process...
aluminium alloy, 8.0Jx18H2 ET45 in size, and shod with (eXtra Load) high performance
tyresA tire or tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground...
, with factory supplies being either
ContinentalContinental AG, internally often called Conti for short, is a worldwide leading German manufacturer of tires, brake systems, vehicle stability control systems, engine injection systems, tachographs and other parts for the automotive and transport industries. The company is based in Hanover, Germany...
SportContact2 or
MichelinMichelin is a tyre manufacturer based in Clermont-Ferrand in the Auvergne région of France. It is one of the two largest tyre manufacturers in the world along with Bridgestone. In addition to the Michelin brand, it also owns the BFGoodrich, Kleber, Riken, Kormoran and Uniroyal tyre brands...
PilotSport PS2.
B6 body & interior
Discrete lower
doorA vehicle door is a partition, typically hinged, but sometimes attached by other mechanisms such as tracks, in front of an opening which is used for entering and exiting a vehicle. A vehicle door can be opened to provide access to the opening, or closed to secure it. These doors are similar to...
trims, along with the now trademark Audi 'S' model vertical-emphasis line
grilleA grille or grill is an opening of several slits side by side in a wall or metal sheet or other barrier, usually to let air or water enter and/or leave but keep larger objects including people and animals in or out.-Spelling:In the United States, "grille" is used to differentiate the automotive...
, and solid
aluminiumAluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
(later replaced with plastic covered by aluminium) exterior
door mirrorsA wing mirror is a mirror found on the exterior of motor vehicles for the purposes of helping the driver see areas behind and to the sides of the vehicle, outside of the driver's peripheral vision .Although almost all modern cars mount their side mirrors on the doors, normally at the "A" pillar,...
, and S4 badging front and rear are all that visually distinguish the S4 from its related A4 brethren. In the interior, front and rear
RecaroRECARO GmbH & Co. KG, commonly known as Recaro, is a German company based in Kirchheim unter Teck in the vicinity of Stuttgart, known for their automobile bucket seats...
seats (fronts fully electric), standard
carbon fibreCarbon fiber, alternatively graphite fiber, carbon graphite or CF, is a material consisting of fibers about 5–10 μm in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in crystals that are more or less aligned parallel to the long axis of the fiber...
trims, as well as S4 logos in the instrument panel and door sills complete the detail.
B7 (Typ 8E/8H, 2005–2008)
The Audi B7 platform
Audi S4 quattro, based on the Audi B7 A4, debuted in late 2005. Although Audi classifies it as a new car, the differences between it and the outgoing B6 S4 casually appear to be primarily cosmetic, and is still classified by the internal designation: Typ 8E (although with revised sub-designations - saloon: 8EC, Avant: 8ED, and Cabriolet: 8HE). It has the same 4.2 litre
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
(identification code: BBK) as the B6 S4, producing a
powerIn physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output of 253 kW at 7,000
revolutions per minuteRevolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
(rpm), and 410 newton metres (302 ft·lbf)
torqueTorque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
at 3,500 rpm.
There are a few mechanical changes, such as revised
springsA spring is an elastic object used to store mechanical energy. Springs are usually made out of spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after fabrication...
and dampers and, from
model yearThe model year of a product is a number used worldwide, but with a high level of prominence in North America, to describe approximately when a product was produced, and indicates the coinciding base specification of that product....
2007, an updated
TorsenTorsen is a type of differential used in automobiles. It was invented by American Vernon Gleasman and manufactured by the Gleason Corporation. Torsen is a contraction of Torque-Sensing...
T-3 automatically biasing centre differential, featuring a 'default' asymmetric 40:60 front-rear torque split on manual transmission models, along with the later
BoschRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
ESP 8.0
Electronic Stability ProgrammeElectronic stability control is a computerized technology that may potentially improve the safety of a vehicle's stability by detecting and minimizing skids. When ESC detects loss of steering control, it automatically applies the brakes to help "steer" the vehicle where the driver intends to go...
and gloss black painted brake calipers. The 'Avus-III'
roadwheelsA wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...
now became an option, and were replaced by a standard offering 8.0Jx18 inch 'S-design' 7-spoke forged
alloy wheelAlloy wheels are automobile wheels which are made from an alloy of aluminium or magnesium. They are typically lighter for the same strength...
.
Bose sound system is now standard, whereas it was optional on the B6 S4, and an enhanced optional
DVD-ROMA DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
-based RNS-E satellite navigation system replaces the previous
CD-ROMA CD-ROM is a pre-pressed compact disc that contains data accessible to, but not writable by, a computer for data storage and music playback. The 1985 “Yellow Book” standard developed by Sony and Philips adapted the format to hold any form of binary data....
-based RNS-D option.
The new
trapezoidIn Euclidean geometry, a convex quadrilateral with one pair of parallel sides is referred to as a trapezoid in American English and as a trapezium in English outside North America. A trapezoid with vertices ABCD is denoted...
al single-frame
grilleA grille or grill is an opening of several slits side by side in a wall or metal sheet or other barrier, usually to let air or water enter and/or leave but keep larger objects including people and animals in or out.-Spelling:In the United States, "grille" is used to differentiate the automotive...
, Bi-
XenonA xenon arc lamp is a specialized type of gas discharge lamp, an electric light that produces light by passing electricity through ionized xenon gas at high pressure to produce a bright white light that closely mimics natural sunlight...
high-intensity discharge lampHigh-intensity discharge lamps are a type of electrical lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc tube. This tube is filled with both gas and metal salts. The gas facilitates the...
(HID) headlamps, L-shaped tail-lamps, quad
exhaustAn exhaust system is usually tubing used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove. The entire system conveys burnt gases from the engine and includes one or more exhaust pipes...
tail pipes, and discrete V8 badging below the side repeater indicators help distinguish the B7 from the previous B6 model.
Audi S4 25quattro
In June 2005, Audi announced a limited edition run of 250 special edition S4 saloon cars, celebrating 25 years of quattro four wheel drive. This exclusive model was called the Audi S4 25quattro. Available only in the
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, and only in Avus Silver, the exterior has unique front and rear bumpers, a
carbon fibreCarbon fiber, alternatively graphite fiber, carbon graphite or CF, is a material consisting of fibers about 5–10 μm in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in crystals that are more or less aligned parallel to the long axis of the fiber...
boot lip spoiler and lower front splitter. 15-spoke DTM alloy wheels, along with optional dealer-fitted 'Audi four-rings' decals for the front doors complete the exterior makeover. Black and grey contrasting interior leathers, along with "quattro" embossed into the
RecaroRECARO GmbH & Co. KG, commonly known as Recaro, is a German company based in Kirchheim unter Teck in the vicinity of Stuttgart, known for their automobile bucket seats...
seats, together with an individually numbered exclusive quattro gear shift knob for the manual-only gearbox define the interior changes.
On the mechanical side, the S4 25quattro was the second Audi, after the B7 RS4 to be fitted with the latest
TorsenTorsen is a type of differential used in automobiles. It was invented by American Vernon Gleasman and manufactured by the Gleason Corporation. Torsen is a contraction of Torque-Sensing...
T-3 asymmetric ATB centre differential for its quattro permanent four-wheel drive system. Under normal grip conditions, this is set with a default rearwards torque distribution bias of 40:60 front to rear, and a maximum of 100% torque can automatically be apportioned to the rear axle (and up to 80% to the front) as conditions warrant. The final drive ratios are 3.889.
B8 (Typ 8K, 2009-)
From November 2008, the latest generation of the 'Audi S4 quattro' (Typ 8K) entered factory production. It is based on the current Audi B8 A4, built on the Volkswagen Group MLB/MLP platform. Unlike the previous B6 and B7 models, the new B8 version will only be available as a four-
doorA vehicle door is a partition, typically hinged, but sometimes attached by other mechanisms such as tracks, in front of an opening which is used for entering and exiting a vehicle. A vehicle door can be opened to provide access to the opening, or closed to secure it. These doors are similar to...
five-
seatA car seat is the chair used in automobiles. Most car seats are made from inexpensive but durable material in order to withstand as much use as possible.-Ergonomy: Lumbar and thigh support:...
saloon (sedan), or a five-door five-seat Avant (estate/wagon). The sport-performance two-door four-seat Cabriolet (
convertibleA convertible is a type of automobile in which the roof can retract and fold away having windows which wind-down inside the doors, converting it from an enclosed to an open-air vehicle...
) mantle is now taken by the current Audi S5. Unlike previous generations of the S4, only the sedan will be imported to the United States and Canada.
Compared to the previous B6/B7 S4 which used a 4.2 litre
V8 engineA V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
, this latest B8 S4 utilises a smaller
displacementEngine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...
3.0 litre TFSI V6 engine, but now with the addition of
forced inductionForced induction is the process of compressing air on the intake of an internal combustion engine . A forced induction engine uses a gas compressor to increase the pressure, temperature and density of the air...
via a Roots-style Eaton mechanical supercharger.
The previous B6/B7 S4s were the top-of-the-line models in North America, ahead of the 3.2L V6 and 4-cylinder 2.0T A4s, and competed with the BMW M3 which at the time had a high-rev 3.2 L inline 6. The 3.0 TFSI V6 engine replaces the 3.2 litre FSI V6 as the upgrade engine in the A4 and A6 lineups starting for 2009; both the 3.2 litre FSI and 3.0 TFSI were offered together until the end of the 2010 model year. The 3.2L V6 engine is no longer offered in the A4 lineup from the 2011 model year onwards, so the recently introduced B8 S4 is now priced 9% lower than its V8 predecessors, and slots directly above the 4-cylinder 2.0T base model. The S4 now compares more closely with the BMW 335i and
Infiniti G37The Infiniti G is a compact executive/entry-level luxury car produced by Nissan's luxury brand Infiniti. The first two generations of the Infiniti G were sedans based on the Nissan Primera. Beginning with its third generation , the Infiniti G have been rebadged versions of the Nissan Skyline line...
, leaving the next incarnation of the
Audi RS4The 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 , produced by Audi's high-performance private subsidiary quattro GmbH, in limited numbers, for German car manufacturer...
to compete with the M3.
Although still badged as an
S modelAudi S and RS models are a range of high performance cars of certain model ranges from the German automotive company AUDI AG. These cars are original equipment manufacturer factory "upgraded" versions of specific cars, from within Audi's standard range of vehicles, primarily focusing in enhanced...
, the B8 S4 is now considered less of a hardcore sport sedan. Enthusiast driver aids are now optional rather than standard, such as active rear differential, active steering and ultra-quick electrically-adjustable shocks (both via Audi Drive Select Package). These trick differentials in the S4 are complex and heavy but they are key to solving the inherent flaw of high-horsepower front-drive vehicles, as the S4's weight distribution remains nose heavy like its predecessors which contributes to
understeerUndersteer and oversteer are vehicle dynamics terms used to describe the sensitivity of a vehicle to steering. Simply put, oversteer is what occurs when a car turns by more than the amount commanded by the driver...
. This allows the S4 to perform competitively with more balanced rear-wheel drive sport sedans such as the BMW 335i.
The S4 has sport suspension tuned for contributing to the vehicle's handling and braking. It is also meant for providing safety and comfort by keeping the vehicle's passengers relaxed and isolated from road noise, bumps and vibrations.
A new designed
roadwheelA wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...
is included on the B8 S4, an 8.5Jx18" '5-double-spoke S' design
alloy wheelAlloy wheels are automobile wheels which are made from an alloy of aluminium or magnesium. They are typically lighter for the same strength...
with 245/40 ZR18 high performance
tyresA tire or tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground...
. Optional 19 inch wheel and tyre packages are also available, sized at 8.5Jx19" alloy wheels with 255/35 ZR19 tyres. LED tail lights are standard fitment, along with Audi's now-trademark LED daytime running lights at the front.
B8 powertrain
At the heart of the B8 S4
powertrainIn a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...
is an all-new, all aluminium-alloy 3.0 litre TFSI
superchargedA supercharger is an air compressor used for forced induction of an internal combustion engine.The greater mass flow-rate provides more oxygen to support combustion than would be available in a naturally aspirated engine, which allows more fuel to be burned and more work to be done per cycle,...
V6 engineA V6 engine is a V engine with six cylinders mounted on the crankcase in two banks of three cylinders, usually set at either a right angle or an acute angle to each other, with all six pistons driving a common crankshaft...
(parts code prefix: 06E, identification code: CAKA), and like the rest of the B8 model range, now with
Fuel Stratified InjectionIn internal combustion engines, gasoline direct injection , also known as petrol direct injection or direct petrol injection, is a variant of fuel injection employed in modern two-stroke and four-stroke gasoline engines...
(FSI). This
petrol engineA petrol engine is an internal combustion engine with spark-ignition, designed to run on petrol and similar volatile fuels....
displacesEngine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...
2998 cc, and it produces a
powerIn physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output of 245 kW from 5,500 to 7,000
revolutions per minuteRevolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
(rpm).
TorqueTorque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
is rated at 440 newton metres (325 ft·lbf) from 2,900 to 5,300 rpm. This high power output is achieved by utilising
forced inductionForced induction is the process of compressing air on the intake of an internal combustion engine . A forced induction engine uses a gas compressor to increase the pressure, temperature and density of the air...
– and specifically, an all-new
EatonEaton Corporation is a global diversified power management company with 2010 sales of $13.7 billion. The company is a leading provider of electrical components and systems for power quality, distribution and control; hydraulics components, systems and services for industrial and mobile equipment;...
'Twin Vortices Series'The TVS Supercharger is an automotive supercharger that was developed by Eaton Corporation to improve on all existing types superchargers. The TVS acronym stands for Twin Vortices Series....
(TVS)
Roots-typeThe Roots type supercharger or Roots blower is a positive displacement lobe pump which operates by pumping fluids with a pair of meshing lobes not unlike a set of stretched gears. Fluid is trapped in pockets surrounding the lobes and carried from the intake side to the exhaust...
positive displacement compressor. This new supercharger features twin four-lobe rotors, which are axially-twisted 160
degreesA degree , usually denoted by ° , is a measurement of plane angle, representing 1⁄360 of a full rotation; one degree is equivalent to π/180 radians...
. It is mounted on top of the engine, within the 'Vee', pumping air directly into the inlet manifold, and incorporates two separate water-cooled
intercoolerAn intercooler , or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged and supercharged internal combustion engines to improve their volumetric efficiency by increasing intake air charge density through nearly isobaric cooling, which removes...
s. This new design of supercharger is said to reduce the
noise, vibration, and harshnessNoise, vibration, and harshness , also known as noise and vibration , is the study and modification of the noise and vibration characteristics of vehicles, particularly cars and trucks...
(NVH) of the engine.
This engine is mated to either a six-speed
manual transmissionA manual transmission, also known as a manual gearbox or standard transmission is a type of transmission used in motor vehicle applications...
(identification code: KMR) or a seven-speed '
S tronicThe Direct-Shift Gearbox , commonly abbreviated to DSG, is an electronically controlled dual clutch multiple-shaft manual gearbox, in a transaxle design - without a conventional clutch pedal, and with full automatic, or semi-manual control...
' DL501
dual clutch transmissionA dual clutch transmission, commonly abbreviated to DCT , is a differing type of semi-automatic or automated manual automotive transmission. It utilises two separate clutches for odd and even gear sets...
(identification code: LHK), the latter with steering wheel mounted paddle-shifters for tiptronic gear selection, which replaces the Tiptronic automatic transmissions found in the B6/B7 iterations. The 'Audi quattro Sports differential' fitted in the rear axle final drive unit is available as an option.
Acceleration from standstill to 100 kilometres per hour (62.1 mph) takes 5.1 seconds for the saloon with manual gearbox, the Avant one tenth of a second slower at 5.2 seconds. The same dash to 100 km/h in the saloon with S tronic takes 5.3 seconds, and the Avant at 5.4 seconds. The top speed is electronically limited to 250 kilometres per hour (155.3 mph). With figures like these, the B8 S4 accelerates more quickly than its V8-engined predecessors. Audi of America claims that the version of the S4 achieves 28 highway miles per gallon, and a 0 to 60 miles per hour (26.8 m/s) acceleration time of 4.9 seconds with the manual transmission and 5.1 seconds with the S tronic. Fuel consumption is rated at a combined 24.2 miles per US gallon. Therefore, the B8 S4, unlike the V8-powered B6/7 models, avoids the US
gas guzzler taxThe National Energy Act: Energy Tax Act of 1978 , or the Gas Guzzler Tax, imposed set tax penalties on car manufacturers who fail to meet the minimum fuel economy level of in the United States. This does not include minivans, sport utility vehicles or pick-up trucks. It is intended to discourage...
. The B8 S4's 3.0 TFSI engine also gets only 1 m.p.g. less than the base 2.0 TFSI engine. This is one of the most important reasons for Audi to downsize their engines, while keeping the output equivalent better, by using forced-induction such as supercharging or turbocharging.
Detuned versions of this same engine making 310 hp are found in the 2009-11 Audi A6 3.0 TFSI (C6) mated to a 6-speed Tiptronic automatic transmission, the 2012 Audi A6 3.0 TFSI (C7) and 2012
Audi A7The Audi Sportback concept is a concept car produced by Audi, shown at the 2009 North American International Auto Show. The Sportback concept, a luxury five-door fastback model, was regarded as a preview of two future models: the Audi A5 Sportback variant and the Audi A7...
3.0 TFSI, the latter two which are paired with an 8-speed Tiptronic automatic.
Motorsport
In
motor racingAuto racing is a motorsport involving the racing of cars for competition. It is one of the world's most watched televised sports.-The beginning of racing:...
,
APR MotorsportAPR LLC is an automotive engineering and motor racing company based in Opelika, Alabama. APR mainly deals with Audi, Porsche and Volkswagen Group brands - Volkswagen, Škoda, and SEAT. Primarily APR is a research and development company that writes proprietary software for reading and writing to a...
has currently entered a B8 S4 in the Grand-Am Continental Tire Sports Car Challenge Grand Sport (GS) class.
External links