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66-474: The Audi V8 ( Typ 4C ) is a four-door, full-size luxury sedan , designed, manufactured and marketed by Audi in Germany from 1988 to 1993, as the company's flagship . As the first car from Audi to use a V8 engine , also was the first Audi to combine a quattro system with an automatic transmission . Early cars used 3.6-litre V8s, while later cars featured a 4.2-litre version of the engine. The Audi V8

132-493: A Torsen type 1 Torque Sensing center differential . The rear axle final drive unit contains a Torsen type 1 Torque Sensing differential, instead of the more common hypoid open differential. Both available engines used a Bosch Motronic fully electronic engine control unit (ECU), with cylinder bank selective knock control, dual-barrel throttle valve, lambda mixture control via intake air volume metering and exhaust gas temperature sensor, and required unleaded petrol . Fuel

198-405: A cable-operated parking brake. A Bosch anti-lock braking system (ABS) was also standard. Standard wheels were 7.5J x 15 H2 ET35 'aero' style light alloy wheels fitted with 215/60 R15 steel-belted radial tyres . Optional multi-spoke BBS -sourced (with Audi centre-cap badge) alloy wheels were also available, in either 8.0J x 16 , or 8.0J x 17 sizes. The Audi V8 came standard with

264-469: A pulsed flow control is wanted. The pulse can be controlled by a combination of differential pressure and spring load as required. Presta and Schrader valves used on pneumatic tyres are examples of poppet valves. The Presta valve has no spring and relies on a pressure differential for opening and closing while being inflated. Poppet valves are employed extensively in the launching of torpedoes from submarines . Many systems use compressed air to expel

330-484: A range of features, including a BOSE audio system with eight speakers, walnut wood trim, leather interior, and heated seats. Some available colors included pearl white, lago blue (teal), blue mica, tornado red and black. All paint finishes were pearlescent or metallic. The lists below details other standard and optional features. Standard features that came with the Audi V8. Optional features that were offered with

396-463: A relative term, full-size cars were marketed by the same brands offering compact cars, with entry-level cars for buyers seeking the roominess of a luxury car at a lower cost. Into the 1970s, the same vehicles could transport up to six occupants comfortably (or eight in a station wagon), at the expense of high fuel consumption. The sales of full-size vehicles in the United States declined after

462-529: A valve gear for double-beat poppet valves in 1842. Criticism was reported in the journal Science in 1889 of equilibrium poppet valves (called by the article the "double or balanced or American puppet valve") in use for paddle steamer engines, that by its nature it must leak 15 percent. Poppet valves have been used on steam locomotives , often in conjunction with Lentz or Caprotti valve gear . British examples include: Sentinel Waggon Works used poppet valves in their steam wagons and steam locomotives. Reversing

528-505: Is present. A choice of transmissions were offered. A ZF Friedrichshafen -sourced four-speed 4HP24A automatic transmission with a torque converter was available throughout the V8 production run. Automatic transmission has three modes: "S" – Sport; "E" – Economic and "M" – Manual operation. St mode changes gears at higher rpms than E; M allows the driver to select gears using the lever. There were also two manual transmission offerings – for

594-734: Is the largest size class for cars. In the United Kingdom, this class is referred to as the executive car , while in Europe, it is known as E-segment or F-segment . The United States Environmental Protection Agency (EPA) Fuel Economy Regulations for 1977 and Later Model Year (dated July 1996) includes definitions for classes of automobiles. Based on the combined passenger and cargo volume, large cars (full-size cars) are defined as having an interior volume index of more than 120 cu ft (3.4 m ) for sedan models, or 160 cu ft (4.5 m ) for station wagons. From

660-604: The D1 or D11 platform. The Audi V8 differed from the Audi 100/200 with a unique grille attached to the hood, new bumpers and headlights, all-red tail lamps, 12 mm extended wheelbase , wider track, pronounced fenders , and more wood trim in the interior. Furthermore, only alloy wheels were offered, ranging from 15 to 17 inches. In addition to the standard-length model, there was also a long wheelbase (LWB), ('Lang' in German) version of

726-572: The Patent Office fire of 1836 destroyed all records of it. The word poppet shares etymology with " puppet ": it is from the Middle English popet ("youth" or "doll"), from Middle French poupette , which is a diminutive of poupée . The use of the word poppet to describe a valve comes from the same word applied to marionettes , which, like the poppet valve, move bodily in response to remote motion transmitted linearly. In

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792-580: The 1908 Ford Model T . In 1923, General Motors introduced the Chevrolet Superior , becoming the first vehicle to adopt a common chassis (the A-body ) for several brands. Compared to the cars of the 21st century, these vehicles are small in length and width. From the 1920s to the 1950s, most manufacturers produced model lines in a single size, growing in size with each model redesign. While the length and wheelbase varied between model lines, width

858-677: The 1985 model year, General Motors replaced most of its full-size rear-wheel-drive model lines with smaller front-wheel drive sedans on the H and C platforms . Only station wagons, the Chevrolet Caprice , and the Cadillac Brougham remained. Initially developed to replace the Ford LTD Crown Victoria, the 1986 Ford Taurus was produced alongside it as the Ford mid-size model line. After largely abandoning

924-517: The 3.6 V8, and the 4.2 unit was identical to the optional V8 used in the Audi S4 (aka Ur-S4 ), sharing the same rated outputs and ABH identification code. Like the 3.6 V8 model, the existing four-speed automatic gearbox remained available. However, a new six-speed manual gearbox replaced the five-speed manual. This powerplant is identified by chrome 'V8' badges on the front grille and at trunk lid, where in some cars also '4.2 quattro' badge

990-405: The 3.6: a five-speed manual gearbox , or later for the 4.2, a six-speed manual. Both manual transmission variants used a 240-millimetre (9.4 in) single-plate clutch . The details of Audi V8 transmission are shown in the table below: The Audi V8 came equipped with rack and pinion power assisted steering (PAS) as standard. An electronically controlled variable assisted 'servotronic' version

1056-460: The 4.2 V8 ( ABH ) had a longer interval at 120,000 kilometres (75,000 mi). A thermostatically controlled electric cooling fan also became standard, replacing the engine-driven viscous fans on earlier cars. This not only provided forced airflow for the engine coolant radiator , but also for the smaller engine oil cooler. Audi's 'trademark' quattro permanent (or semi-permanent, dependent on gearbox type) four-wheel drive system

1122-605: The Audi Forum Ingolstadt, but in storage in Neckarsulm. Powertrain detail of the Audi V8 featured one of two all-new, all- aluminium alloy engines – both petrol engines , and both in V8 configuration with 32 valves (four valves per cylinder ) with dual valve springs , and four overhead camshafts (DOHC). The design set the pattern for future Audi-developed Volkswagen Group V8 engines . In addition to using an all-aluminum alloy cylinder block (when

1188-434: The Audi V8 included a 32-valve , double overhead camshaft (DOHC) V8 engine and a four-speed electronically controlled ZF 4HP24A automatic transmission providing Audi's quattro permanent four-wheel drive system. A five-speed (later in production six-speed) manual transmission was also available. The Audi V8 had a galvanized steel body, with a 10-year anti-perforation warranty (against corrosion ). The Audi V8

1254-519: The Audi V8. Audi developed a Group A competition version of the Audi V8 for entry into the Deutsche Tourenwagen Meisterschaft (DTM) (German Touring Car Championship) auto racing series equipped with a 309  kW (420  PS ; 414  bhp ), later 340  kW (462  PS ; 456  bhp ), 3.6 V8 engine and 6-speed manual transmission, and began racing with it in 1990 with Schmidt MotorSport (SMS) running

1320-656: The Chevrolet Impala was returned for the 1994 model year. The 1989 Lexus LS400 luxury sedan was the first Japanese full-size car sold in North America. Following the 1996 model year, GM ended production of large rear-wheel drive sedans. By 2000, with the sole exception of the Ford Crown Victoria, Mercury Grand Marquis, and Lincoln Town Car, full-size cars had abandoned rear-wheel drive and body-on-frame construction. Instead of model lineage,

1386-798: The EPA "large car" definition of over 120 interior cubic feet was widely used. Initially developed for the midsize Oldsmobile Aurora , the GM G-body chassis was expanded into the full-size segment for Cadillac in 2000 (for the Deville, later the DTS) and adapted by Buick (the Lucerne) in 2006. For the 2005 model year, Chrysler replaced the LH cars with the LX cars (returning to rear-wheel drive). The same year, Ford introduced

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1452-702: The Five Hundred, its first front-wheel drive full-size car (the first American full-size car offered with all-wheel drive); in 2008, the Five Hundred was renamed the Taurus. After the 2011 model year, Ford ended production of the Panther platform, shifting to the Ford Taurus and Lincoln MKS; in 2017, the latter was replaced by the Lincoln Continental . In 2011, General Motors ended production of

1518-559: The G-body for several chassis (with Cadillac later shifting its largest sedans to rear-wheel drive). In 2012, the Tesla Model S became the first fully electric full-size car sold in North America. For the 2013 model year, the Chevrolet Impala became the final American-market full-size sedan sold with a front bench seat . By the mid-2010s, full-size cars began seeing a steep decline in sales in North America, with SUVs replacing much of

1584-569: The V8 (refer to the infobox for differences in dimensions). It was assembled at Steyr-Daimler-Puch factory in Graz (see production figures ). This tradition would continue with the A8, offered in "A8L" format (though only in year 2010 A8L reached the size of the V8L). A once-off experimental Avant (estate) version was built for the wife of former Audi CEO Ferdinand Piech . This car is no longer on display at

1650-684: The car was a cornerstone in developing the history of the Audi marque as it is today. Factory production commenced in October 1988, and ceased in November 1993, although sales of completed vehicles continued in 1994. It was replaced by the Audi A8 in 1994. The Audi V8 used an enlarged version of the bodyshell from the Typ 44 Audi 100 and 200 models, and was based on a stretched version of their Volkswagen Group C3 automobile platform , known either as

1716-521: The chamber being sealed. The shaft travels through a valve guide to maintain its alignment. A pressure differential on either side of the valve can assist or impair its performance. In exhaust applications higher pressure against the valve helps to seal it, and in intake applications lower pressure helps open it. The poppet valve was invented in 1833 by American E.A.G. Young of the Newcastle and Frenchtown Railroad . Young had patented his idea, but

1782-443: The championship. During its presence at DTM the Audi V8 competed with much smaller and about 300 kg (661 lb) lighter Mercedes 190 , BMW M3 , and slightly smaller Opel Omega 3000 . None of those cars were equipped with V8 engines or 4-wheel drive. Full-size Full-size car —also known as large car —is a vehicle size class which originated in the United States and is used for cars larger than mid-size cars . It

1848-416: The cylinder. Use of automatic valves simplified the mechanism, but valve float limited the speed at which the engine could run, and by about 1905 mechanically operated inlet valves were increasingly adopted for vehicle engines. Mechanical operation is usually by pressing on the end of the valve stem, with a spring generally being used to return the valve to the closed position. At high engine speeds ( RPM ),

1914-528: The early 1970s fuel crisis. In response to the 1978 implementation of CAFE , American manufacturers implemented downsizing to improve fuel economy, with full-size vehicles as the first model lines to see major change. While General Motors and Ford would reduce the exterior footprint of their full-size lines to that of their intermediates, AMC withdrew its Ambassador and Matador full-size lines (to concentrate on production of mid-size vehicles). To save production costs, Chrysler repackaged its intermediates using

1980-448: The erstwhile full-size names, moving on to exiting the segment in 1981. During the 1980s, manufacturers further reduced the exterior footprint of several model lines from the full-size segment into the mid-size class to comply with more stringent CAFE standards. With the 1982 model year, Chrysler exited the full-size segment entirely, with the mid-size Dodge Diplomat and Plymouth Gran Fury serving as its largest sedan lines. Following

2046-429: The established material was grey cast iron ), the camshafts were driven using a hybrid method. A rubber / kevlar toothed timing belt , driven from the front of the crankshaft operated only the exhaust camshaft in each bank. The inlet camshafts were then operated via a simplex roller chain from the exhaust camshaft – the right bank, (cylinders 1–4) at the rear of the engine, and the left bank (cylinders 5–8) at

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2112-468: The exhaust valve remains beside the cylinder in an upside down orientation. These designs were largely replaced by the overhead valve (OHV) engine between 1904 until late-1960s/early-to-mid 1970s, whereby the intake and exhaust valves are both located directly above the cylinder (with the camshaft located at the bottom of the engine). In turn, OHV engines were largely replaced by the overhead camshaft (OHC) engines between 1950s until 1980s. The location of

2178-625: The first time since the late 1970s. For the 1992 model year, Chrysler introduced a new front-wheel drive full-size car line, replacing the Eagle Premier/Dodge Monaco with the Chrysler LH cars (Dodge Intrepid, Eagle Vision, Chrysler Concorde/New Yorker/LHS). The same year, the Buick Roadmaster was introduced, becoming the first rear-wheel drive GM model line adopted outside of Chevrolet and Cadillac since 1985;

2244-401: The force required to open them. This has led to the development of the balanced poppet or double beat valve , in which two valve plugs ride on a common stem, with the pressure on one plug largely balancing the pressure on the other. In these valves, the force needed to open the valve is determined by the pressure and the difference between the areas of the two valve openings. Sickels patented

2310-436: The front of the engine, immediately behind the timing belt. This method reduced the complexity of the timing belt layout, and as a result, required fewer components, such as idler rollers and guides, and led to easier and less costly maintenance of the timing belt and associated components. The intervals for changing the timing belts varied; the 3.6 V8 ( PT ) required changing every 90,000 kilometres (60,000 mi), whereas

2376-550: The full-size sedan category in the United States were the Dodge Charger, Chevrolet Impala, and Chrysler 300. The large car segment has been declining in the United States accounting for 3.6% of new vehicle sales in 2021, down from 6.6% in 2016. The models in this category included the Chrysler 300, Dodge Charger, Nissan Maxima, and Toyota Avalon. They have been discontinued after the 2023 or 2024 model years. The trend in

2442-583: The full-size segment for compact cars and minivans, Chrysler gained reentry into the full-size segment in 1988 with the Eagle Premier (also produced as the Dodge Monaco ). Developed by AMC before its acquisition by Chrysler, the Premier was a version of the front-wheel drive Renault 25 adapted for North America. The Saab 9000 took a special position at the end of the 1980s, as for a long time it

2508-477: The full-size segment. At the end of the decade, demand for sedans (of all sizes) shifted towards vehicles of other layouts, reducing or shuttering production of sedans entirely. In 2018, Ford announced the sales of all Ford-branded passenger cars (except for the Mustang ) would end in North America by 2022. General Motors announced the closure of several manufacturing facilities in the United States and Canada, with

2574-409: The hot valve head to the stem where it may be conducted to the cylinder head. Common in second world war piston engines, now only found in high performance engines. Early engines in the 1890s and 1900s used an "automatic" intake valve, which was opened by the vacuum in the combustion chamber and closed by a light spring. The exhaust valve had to be mechanically driven to open it against the pressure in

2640-491: The introduction of the Ford Flathead V8 in the 1930s until the 1980s, most North American full-size cars were powered by V8 engines . However, V6 engines and straight-six engines have also been available on American full-size cars, especially until the 1950s, and have become increasingly common since the downsizing of full-sized cars in the 1980s. The lineage of mass-produced full-size American cars begins with

2706-450: The large car market segment in United States is toward the SUV. Intake valve It consists of a hole or open-ended chamber, usually round or oval in cross-section, and a plug, usually a disk shape on the end of a shaft known as a valve stem. The working end of this plug, the valve face, is typically ground at a 45° bevel to seal against a corresponding valve seat ground into the rim of

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2772-470: The operation, and Hans-Joachim Stuck , Walter Röhrl and Frank Jelinski driving. In the 1990 DTM season all of the three teams claimed together the entire podium (1st, 2nd and 3rd places) at Hockenheimring race. Stuck won the title, and the following year, Audi added a second team to the mix, Audi Zentrum Reutlingen (AZR). SMS continued with Stuck and Jelinski, while AZR raced with Frank Biela and Hubert Haupt . Biela gave Audi another crown in 1991 , but

2838-410: The past, "puppet valve" was a synonym for poppet valve ; however, this usage of "puppet" is now obsolete. The poppet valve is different from both slide and oscillating valves. Instead of sliding or rocking over a seat to uncover a port, the poppet valve lifts from the seat with a movement perpendicular to the plane of the port. The main advantage of the poppet valve is that it has no movement on

2904-544: The poppet valve which sits inside the combustion chamber is a flat disk, while the other side tapers from the disk shape to a thin cylindrical rod called a "valve stem". In a typical modern mass-production engines, the valves are solid and made from steel alloys . However some engines use hollow valves filled with sodium , to improve heat transfer . Many modern engines use an aluminium cylinder head. Although this provides better heat transfer, it requires steel valve seat inserts to be used; in older cast iron cylinder heads,

2970-472: The production of the Chevrolet Impala and Buick LaCrosse ending in 2020. As of 2022, full-size cars from Asian manufacturers include the Lexus LS , Genesis G80 / G90 , Nissan Maxima , and Toyota Avalon . Another car from an Asian manufacturer, the eighth-generation Hyundai Sonata , is classified by the EPA as full-size despite being marketed as a mid-size model. In 2018, the three highest-selling cars in

3036-455: The seat, thus requiring no lubrication. In most cases it is beneficial to have a "balanced poppet" in a direct-acting valve. Less force is needed to move the poppet because all forces on the poppet are nullified by equal and opposite forces. The solenoid coil has to counteract only the spring force. Poppet valves are best known for their use in internal combustion and steam engines, but are used in general pneumatic and hydraulic circuits where

3102-449: The throttle is abruptly closed. Historically, valves had two major issues, both of which have been solved by improvements in modern metallurgy . The first was that in early internal combustion engines, high wear rates of valves meant that a valve job to regrind the valves was required at regular intervals. Secondly, lead additives had been used in petrol (gasoline) since the 1920s, to prevent engine knocking and provide lubrication for

3168-417: The torpedo from the tube , and the poppet valve recovers a large quantity of this air (along with a significant amount of seawater) in order to reduce the tell-tale cloud of bubbles that might otherwise betray the boat's submerged position. Poppet valves are used in most piston engines to control the flow of intake and exhaust gasses through the cylinder head and into the combustion chamber . The side of

3234-432: The twisting path of the intake and exhaust gasses had major drawbacks for the airflow, which limited engine RPM and could cause the engine block to overheat under sustained heavy load. The flathead design evolved into intake over exhaust (IOE) engine , used in many early motorcycles and several cars. In an IOE engine, the intake valves were located directly above the cylinder (like the later overhead valve engines ), however

3300-466: The valve seats are often part of the cylinder head. A gap of 0.4–0.6 mm (0.016–0.024 in) is present around the valve stem, therefore a valve stem oil seal is used to prevent oil being drawn into the intake manifold and combustion chamber. Typically, a rubber lip-type seal is used. A common symptom of worn valve guides and/or defective oil seals is a puff of blue smoke from the exhaust pipe at times of increased intake manifold vacuum , such as when

3366-466: The valves is broadly the same between OHV and OHC engines, however OHC engines saw the camshaft located to the top of the engine with the valves and OHC engines often have more valves per cylinder. Most OHC engines have an extra intake and an extra exhaust valve per cylinder (four-valve cylinder head), compared with the design of two valves per cylinder used by most OHV engines. However some OHC engines have used three or five valves per cylinder. James Watt

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3432-454: The valves, via several intermediate mechanisms (such as pushrods , roller rockers and valve lifters ). The shape of the cams on the camshaft influence the valve lift and determine the timing of when the valves open. Early flathead engines (also called L-head engines ) saw the valves located beside to the cylinder(s), in an "upside down" orientation parallel to the cylinder. Although this design made for simplified and cheap construction,

3498-462: The valves. Modern materials for the valves (such as stainless steel) and valve seats (such as stellite ) allowed for leaded petrol to be phased out in many industrialised countries by the mid-1990s. Exhaust valves are subject to very high temperatures and in extreme high performance applications may be sodium cooled. The valve is hollow and filled with sodium, which melts at a relatively low temperature and, in its liquid state, convects heat away from

3564-405: The weight of the valvetrain means the valve spring cannot close the valve as quickly enough, leading to valve float or valve bounce . Desmodromic valves use a second rocker arm to mechanically close the valves (instead of using valve springs) and are sometimes used to avoid valve float in engines that operate at high RPM. In most mass-produced engines, the camshaft (s) control the opening of

3630-450: Was DIN -rated with a maximum motive power output of 184 kilowatts (250  PS ; 247  bhp ) at 5,800  revolutions per minute (rpm), and generated a torque turning force of 340 newton-metres (251  lbf⋅ft ) at 4,000 rpm. In August 1991, Audi introduced a 4.2-litre engine, displacing 4,172 cubic centimetres (254.6 cu in), to complement the choice of the existing 3.6-litre V8. This shared many components from

3696-581: Was a relatively constant dimension, as the American federal government required the addition of clearance lights on a width past 80 inches. In 1960, following the introduction of compact cars (such as the Chevrolet Corvair , Ford Falcon and Plymouth Valiant ), the "full-size car" designation came into wider use. In the 1960s, the term was applied to the traditional car lines of lower-price brands, including Chevrolet, Ford, and Plymouth. As

3762-660: Was achieved by a simple sliding camshaft system. Many locomotives in France, particularly those rebuilt to the designs of Andre Chapelon, such as the SNCF 240P , used Lentz oscillating-cam poppet valves, which were operated by the Walschaert valve gear the locomotives were already equipped with. The poppet valve was also used on the American Pennsylvania Railroad 's T1 duplex locomotives , although

3828-504: Was also available. It was fitted with a high-performance brake system, which included radially ventilated disc brakes front and rear. The fronts were rather unusual – designed by Continental AG and sized at 310 millimetres (12.2 in) in diameter by 25 millimetres (0.98 in) thick, but the caliper was mounted inside the disc. The fronts also incorporated electronic brake pad wear sensors. The rears were 269 millimetres (10.6 in) by 20 millimetres (0.79 in), and incorporated

3894-417: Was delivered to the combustion chambers via eight intake manifold -sited electronic fuel injectors , fed from two common fuel rails (one per cylinder bank), and were sequentially 'fired' or activated in accordance with the engine's firing order . Whilst the 3.6 V8 was able to use 95  RON (91  AKI ) fuel, for the 4.2 V8, the more expensive 98 RON (93 AKI) 'SuperPlus' unleaded

3960-399: Was replaced by the Audi A8 in 1994, although the A8 was not marketed in North America until 1996. The competition model of the Audi V8 won back-to-back Deutsche Tourenwagen Meisterschaft driver's titles in 1990 and 1991, with the championship winners being Hans-Joachim Stuck and Frank Biela respectively. Audi was the first company to win back-to-back DTM titles. Standard features for

4026-462: Was required in order to achieve the quoted power output. The usage of 95 RON in the 4.2 V8 resulted in a lower power output, as well as increased fuel consumption. At the initial launch of the Audi V8, the only offering was the 3.6-litre powerplant, which displaced 3,562 cubic centimetres (217.4  cu in ). This V8 engine was derived from the 1.8 16V engine from the Golf GTI. It

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4092-400: Was specifically designed to be a top of the range ' flagship ' car and included a number of luxury features as standard equipment, including leather seating and Audi's quattro all wheel drive system (see standard features list ). The Audi V8 created a new elevated image for the company, providing a viable alternative to established competitors such as Mercedes-Benz and BMW . In this regard,

4158-425: Was the only imported car to be classified as a "large car" by the EPA. From the 1980s to the 1990s, the market share of full-size cars began to decline; along with the increased use of mid-size cars, vans, and SUVs grew in use as family vehicles. Between 1960 and 1994, the market share of full-size cars declined from 65 to only 8.3 percent. From 1990 until 1992, both GM and Ford redesigned its full-size car lines for

4224-407: Was the only offering for the drivetrain. This normally distributes the engine torque as a 'default' 50:50 between front and rear axles, but can automatically dynamically apportion up to a bias of 20:80 to 80:20 front and rear. The automatic transmission utilizes a hydraulically controlled multi-plate clutch to apportion drive between front and rear axles, whereas the manual transmission variants utilize

4290-432: Was unable to defend the title in 1992 . For the 1992 season , Audi had changed their engines to use a 180° flatplane crankshaft , which they said had been re- forged and bent from the original 90° crossplane part as used in production model. The DTM organisers found this highly modified crankshaft deviated from original homologated standard crankshaft, and therefore deemed it illegal. Audi subsequently withdrew from

4356-533: Was using poppet valves to control the flow of steam into the cylinders of his beam engines in the 1770s. A sectional illustration of Watt's beam engine of 1774 using the device is found in Thurston 1878:98, and Lardner (1840) provides an illustrated description of Watt's use of the poppet valve. When used in high-pressure applications, for example, as admission valves on steam engines, the same pressure that helps seal poppet valves also contributes significantly to

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