The second making S4 debuted in 1997 as part of the B5 platform A4 line-up, though it wasn’t accessible in North America until year 2000. The B5 S4 had a 2.7 L, twin-turbocharged V6 engine producing 265 PS (195 kW/261 hp) in European trim. The engine was a little detuned to meet US emissions policy, and power closed at 250 hp / 258 ft.lbs. Torque in North America. Audi S4 Avant

In addition to the sedan, a wagon edition, the Audi S4 Avant, was introduced into the assemble from 1998. The S4 could speed up up to 100 km/h (62 mph) in a mere 5.6 seconds and had an electronically-limited top pace of 250 km/h (155 mph), making it both the fastest sedan in the Audi model line and amongst the quickest sedans in the world at that point in time. As in the previous S4, a six-speed manual transmission was average gear, as was the quattro all-wheel-drive. A five-speed Tiptronic transmission became existing for the first time as an opportunity. Production stopped on the B5 S4 in 2001 although it was still sold collectively with the next B6 platform production through 2002 in North America.

The B5 S4 has a loyal enthusiast community that focuses on conquering supercar-level supremacy and presentation. Currently, the B5 S4 is considered the most potentially controlling of the S4 lineup although the stock K03 turbos were prone to early death, it is a much more hard engine to work on than the original S4 (the UrS4), and there is doubt about the ability of the stock engines to handle more than than 1.6 Bar of Boost, that potential has not been confirmed. Being a turbocharged car, it can gain noteworthy power by simply upgrading the engine organization software (commonly referred to as Stage 1) yielding upwards of 330 hp using humble increases in Boost. Extra flow enhancements in Exhaust and Downpipes increased a further 20~30 hp (referred to as Stage 2 and 2+ respectively). By replacing the KKK K03 turbos with the slightly larger B5 RS4′s K04 turbos, as well as other air/fuel delivery components (commonly referred to as Stage 3), aftermarket and house tuners can easily boost power towards the 450 hp (335 kW) range using off-the shelf kits and parts. Due to its extremely tight engine bay, and engine-rearwards turbo placement, alternatives to Audi/KKK turbos have been slow in coming, however almost 10 years after its preamble products are appearing that enable over 500 hp
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