There was a certain magic about Audi’s B5-generation S4, the twin-turbo V6-powered model built up until 2002. Forced induction in an all-wheel-drive sedan was a novel concept in the days before the rally-inspired Subaru WRX and Mitsubishi Evo hit American shores. The car was fast and agile in stock form; more important in the eyes of many was the fact that power could be dialed up to supercar levels for not a whole lot of money thanks to a burgeoning aftermarket. When the S4 moved to big V8 power it became a much better turn-key sport sedan, but those looking for a more refined take on the frenetic rally car concept were left cold. Fortunately, forced induction has returned to the current S4 — this time in supercharged form &mash; and the aftermarket is once again turning up the heat. One of the first to market with a line of upgrades was MTM, who recently handed us the keys to their blisteringly fast B8 S4 Avant to log some time on the nearby A9 autobahn.
From the outside, MTM’s Ibis White S4 Avant is just what we’ve come to expect from the firm. Exterior modifications are minimal with no aerodynamic clutter. A bit of silver trim has been resprayed red and there are the Porsche GT3 RS-style decals on the sides serving notice that it’s both supercharged and from MTM . Wheels have been upgraded to the company’s 20-inch machined, forged and oft-copied BiMoto alloys. An offset of 42 mm on this nine-inch-wide wheel, combined with 10 mm spacers, makes for the perfect fender filling.You’ll note a lower stance as well; MTM’s suspension development partner is KW, and the Avant sports the partnership’s latest coilovers. Height is adjustable from 10 to 40 mm lower than stock up front and 15 to 45 mm lower in the rear.
Under the hood, only two modifications bump the car’s output. First is a tuned ECU wearing the M-Cantronic name. The new designation is a trademark for MTM, deriving its nomenclature from the CAN-bus system within the S4 that networks various ECUs within the car. M denotes engine (motor) changes, while F-Cantronic is used for suspension (fahrwerke) software changes; further packages are planned for elements like the butterfly flaps used in exhaust system.
Our demo car paired the ECU with MTM’s own exhaust upgrade — a freer flowing all-stainless cat-back system featuring quad pipes and throttle-linked valves for on-demand roar. With just these two components in place MTM rates the new S4 at 430 hp and 380 lb-ft of torque, an increase of 97 and 55, respectively. This ‘Stage 1’ upgrade gets owners within spitting distance of the expected 450 hp rating of Audi’s upcoming RS 5. Eventually MTM will develop higher stages of tune with further hardware upgrades that will easily surpass the factory’s own performance benchmark.
To cope with the added power, MTM also upgraded the brakes on this particular Avant with their own eight-piston 380 mm setup, sourced from Brembo, and stainless brake lines.
Firing up the S4, the aggressive exhaust note instantly informs us this car is no longer powered by the melodic V8. There’s more of a bark and, while we’re admittedly very picky about loud aftermarket exhausts, we were very surprised at just how composed the MTM exhaust note was. This may be due in part to the as-advertised valves aiding in the minimization of any drone or obnoxious sound level.
Out on the A9 the power is very impressive. Delivery is smooth and thus deceptively fast on up to 120 mph, which is about where we hit traffic. The car is notably quicker than a stock V8 S5 we drove earlier in the day. In Germany, station wagons aren’t quite the sleepers they are in the States, and the wheels and graphics don’t do much to lower the car’s profile as we bomb the left lane of the autobahn in near rush-hour traffic. MTM claims a 0-62 mph time of 4.7 seconds, 0.2 seconds quicker the last-generation RS 4; they can remove the top speed limiter on the car as well, no doubt his is a higher priority for their German clientele than us Americans.
Demand for S4 upgrades will certainly be huge. Given MTM’s close proximity to Audi in Ingolstadt, and owner Roland Mayer’s own history and connections within the Audi factory, we’re not surprised to see the firm come forth as one of the first with a package for the new S4. No doubt their competitors are not far behind.