The Audi A4 is a compact luxury car made by Audi . It was introduced for the 1996 model year, replacing the Audi 80 (called Audi 90 in North America ).
B5 (1995-1998)
Audi debuted the model in 1995 as a 1996 model on Volkswagen's B5 platform, which it shared with the fifth generation Passat . Like the Passat, it had a longitudinal engine orientation and standard front wheel drive , although the vast majority of A4s Audi sells come optioned with their Quattro all-wheel-drive system.
A wide range of engines were available to European customers including a 1.9 litre diesel 4-cylinder, although Audi's 2.8 litre 12-valve V6, carried over from the old 80/90 was the only engine option in North America until 1998 .
Audi also debuted their new Tiptronic transmission on the B5 platform, based on the unit Porsche developed for their 964-generation 911 . The transmission is a "manumatic", meaning it offers the driver a choice of driving the car as either an automatic or a clutchless manual.
B5 facelifted (1998-2002)
Audi refreshed the model for 1998, replacing the aging 12-valve V6 with a new 2.8 litre unit sporting 5 valves per cylinder, helping bring output to 195 Horsepower from the old engine's 175. Audi also introduced their new "1.8T" for 98', a 1.8 litre, turbocharged 4-cylinder based on the unit they'd developed for their BTCC race car. It made 150 Horsepower and 155 Lb. Ft. of torque until 2001 when Audi updated it, bringing output up to 170 Horsepower. New taillights, headlights , and minor interior changes rounded out the cosmetic updates.Audi re-introduced their high-performance S4 on the B5 platform and debuted an even higher performance RS4 model.
B6 (2002-2005)
A completely redesigned A4 debuted for the 2002 model year, now riding on the B6 platform. The new vehicle retained the 1.8T without changes, but European-market diesels got updates to boost smoothness and power output and the 2.8 litre V6 was replaced by a new 3.0 litre unit making 225 Horsepower.
For 2003 Audi re-intoruced the S4, now powered by a V8, as well as a 2-doored convertible variant of the A4, finally replacing the 80/90 convertible that had been discontinued in 1998 ( 1995 in North America).
Audi also introduced a continuously variable transmission , which replaced the Tiptronic on front wheel drive models. The transmission won considerable praise from automotive press and is generally regarded as being the best of it's type in the world ahead of unit's from other large manufacturers like Toyota .
B7 (2005-onwards)
Audi introduced the next new A4 in late 2005 , now riding on the B7 platform, which is completely unique to Audi and not shared with Volkswagen. Nonetheless, the B7 is really a revision of the outgoing B6, and not a ground-up redesign.
Audi has kept several diesel powerplants available in the European lineup, but has again decided on a 2-engine strategy for the American market. An all-new 2.0 litre, DOHC turbo 4-cylinder with direct injection and making 200 Horsepower and 207 Ft. Lbs of torque replaces the 1.8T, while a new 3.2 litre, 255 Horsepower V6 also with direct injection replaces the 3.0. Quattro drive is available throughout the range on almost all engines.
In addition to the carry-over S4, Audi has re-introduced the RS4 to the lineup.
Audi S4
The Audi S4 is a high performance sport version of the popular Audi A4 .
First generation
Audi was re-configuring its lineup during the early 1990s, and introduced the S4 in 1991 (as a 1992 model) as the performance version of the re-styled 100 sedan. Despite sharing its basic structure with the 100, the S4 effectively took the place of the the 200 Turbo-Quattro sedan, which had been discontinued the year before.
The S4 was sold worldwide with a turbocharged version of Audi's 2.2 litre, 20-valve inline 5-cylinder engine developing 227 Horsepower and 258 Ft. Lbs. of torque. A 280 Horsepower 4.2 litre V8 became available to European customers as an option. Quattro all-wheel-drive and a manual transmission (six-speed in Europe, five-speed in North America ) were standard equipment.
After Audi dropped the 100 nameplate and re-badged the car as A6 in 1994 , the S4 became the S6 , although the only real changes to the model were minor cosmetic updates and the addition of a more powerful S6 Plus model to the lineup. After the 1st generation A6 was replaced in 1998 by an updated version, the S4 and S6 became distinctly seperate from one another.
Second generation (2000-2002)
The second generation S4 debuted in 1999 (as a 2000 model) as part of the B5 platform A4 line-up. Although the S4 was no longer available with a V8, its 2.7 litre, twin-turbocharged V6 engine was more than adequate, producing 265 hp (195 kW) in European trim and 250 hp (184 kW) in North America.
In North American trim, the vehicle could hit 60 miles per hour in a mere 5.5 seconds and had a governor-limited top speed of 155 miles per hour, making it among the quickest sedans in the world at the time.
As in the previous S4, a six-speed manual transmission was standard equipment, as was Quattro. A five-speed Tiptronic transmission became available for the first time as an option. The B5 S4 was produced through the mid- 2002 model year.
Third generation (2004-2005)
The third generation, B6 platfrom S4 debuted in mid- 2003 as a 2004 model. Despite having moved to yet another entirely new platform, the S4's most publicized new feature was its engine.
Replacing the 2.7 litre turbocharged engine of the previous generation S4 was a 4.2 litre, 40-valve (five per cylinder) V8 based on the unit from the A8 and producing 340 Horsepower, making it more potent than either the S6 Plus or RS2 and nearly as powerful as the B5 platform RS4 .
With such abundant power on tap, the B6 S4 could acclerate quickly enough to meet or beat the times of most sports cars. Road tests conducted by American automotive magazines indicated that it could go from a standstill to 60 miles per hour in 5.0-5.2 seconds, and make it to 124 miles per hour in only slightly over 20 seconds.
Like its predecessors, the model was standard with a six-speed manual and Quattro, the Tiptronic transmission remained an option. The B6 platform S4 was replaced by the B7 platform S4 in late- 2005 .
Fourth generation (2006-?)
The B7 platform S4 is the most recent version of the vehicle, having debuted in late 2005 as a 2006 model. Although Audi classifies it as a new car, the differences between it and the outgoing B6 S4 are primarily cosmetic. Audi has, however, made a few notable changes, including changing to new springs and dampers and re-calibrating the Quattro system to maintain a 40:60 front-to-rear torque split under normal conditions. The system is continuously adjustable though, and the torque split can change depending on road conditions, speed, etc... The new "fish mouth" grill, narrow headlamps, "L" tail-lamps and quad exhaust tips help distinquish the B7 from the previous B6 model.