The exterior differences between the Audi 2008 A4 and the quicker Audi S4 may not be drastic, but the changes under the hood certainly are. A bigger, more powerful engine and revised suspension tuning make the 2008 Audi S4 a supremely capable high-performance luxury car.
When Audi upgraded the powerplant in its 2004 model, the S4 was definitely one of the su-perpowers in what Edmunds says is not just a market segment, but "a gosh-darn arms race." And although current models of the BMW M3 and the Mercedes C63 AMG outgun the Audi 2008 S4, they do so at a higher cost, making the Audi S4 definitely worth a look.
Edmunds reports that while the engine bay of the 2008 Audi S4 might be small, it “is fitted with a 4.2-liter 340-hp V8” that Cars.com says “produces 302 pounds-feet of torque at 3,500 rpm." MyRide.com reports that when they ran "the S4 hard through the gears...triple-digit speed comes quickly, the sensation masked by a wide, flat, linear power curve from an engine that doesn't build velocity at the same rate that it builds revs." Other reviews read by TheCarConnection.com similarly praise Audi’s spectacular V-8, and Cars.com reviewers claim the 2008 Audi S4 “can accelerate from zero to 60 mph in 5.3 seconds.” ConsumerGuide doesn’t doubt that figure and agrees “S4s are rapid” and “plenty fast.” Car and Driver also loves the “honking V-8 power and noise” that accompanies the Audi S4.
The 2008 Audi S4 comes with a pair of transmission choices—for driving purists, Edmunds says there is “a six-speed manual gearbox,” while Audi also offers “a six-speed Tiptronic automatic” that “allows manual-style shifting via steering-wheel-mounted paddles” for those drivers who can’t be bothered to use their left foot. Edmunds adds that “the Quattro all-wheel-drive system” is standard on the S4, though unlike other Audis, “it has a 40/60 front-to-rear power split in normal situations to give the car a more dynamic attitude when cornering.” Reviewer impressions of both transmissions are positive, and Kelley Blue Book calls the Quattro system “a perfect match for the engine,” as it “does an exemplary job of delivering the V8’s remarkable output to all four wheels.” MyRide.com finds “the shifter abruptly bangs from gear to gear” when driving the S4 quickly, describing the linkage as “rarely smooth but always authoritative,” and with an “easy clutch.”
A big V-8 engine might bring a low 0-60-mph time, but it also means another low number for this 2008 Audi S4—fuel economy. The official EPA estimates for the 2008 Audi S4 are a bit shocking, with the manual transmission returning 13 mpg in the city and just 20 mpg on the highway, while the six-speed automatic gets 14 mpg city, 21 mpg on the open road. Real-world testing seems to bear those numbers out, as ConsumerGuide reports that their “S4 sedans averaged 16.1-18.4 mpg.”
The aging Audi S4 may no longer be the quickest car in its class, but it can still compete with the latest offerings from BMW and Lexus when it comes to handling and ride quality. ConsumerGuide is pleased to report that the 2008 Audi S4 lineup is “stiff but seldom punishing and [shows] impressive high-speed stability.” Other reviewers simply rave about the cornering ability of the 2008 Audi S4, which Kelley Blue Book says is “simply far beyond most drivers’ previous automotive experiences,” and “even those with considerable time in very high-performance cars will likely be seriously impressed.” The one performance draw-back noted in some reviews read by TheCarConnection.com is captured by Car and Driver reviewers, who lament “the S4’s resolute understeer,” and MyRide.com feels that the “steering [is] much too light.” Edmunds, however, loves how the 2008 Audi S4 manages to offer “excellent handling while still providing a supple ride.” MyRide.com does end on a positive note, finding that “the brakes are great” on the 2008 Audi S4.