For the torquey wagon, subtle changes are possible.

ABT recently acquired a facelifted Audi S6 Avant to play with its diesel engine. Now it’s doing so with the smaller brother, theS4. The recently redesigned performance Avant from Audi Sport is also equipped with a diesel engine. It has been stripped of its stock wheels to make way for the tuner’s 20-inch set. This sets features a black diamond-machined finish for greater visual impact.

A new suspension kit by ABT has been developed to lower the ride height of the wagon’s shoes from 15 to 40 millimeters (0.6-1.6 inches). To improve handling and speed through corners, the Audi wagon that runs on diesel has a high-tensile anti-roll bar made of spring steel. The Kempten-based tuner keeps things subtle so that you don’t know if the car has changed.

All this sounds great, but what about more power. It has. The electrified 3.0-liter V6 TDI now produces 342 horsepower and 516 pound feet (700 Newton-meters) more torque than the original engine. The ABT’s customized engine control unit has helped to massage the engine, resulting in 378 horsepower and 560 lb-ft (760Nm).

The extra 36 horsepower and 45 lb-ft (61Nm) have significantly improved the performance of the S4 Avant. It takes just 4.7 seconds to reach 62 mph (100 km/h), which is only two tenths less than the stock model. This upgrade to the sedan results in a sprint time that is only 4.6 seconds. This is half a second less than the RS4 avant, the crown jewel of the A4 lineup.

ABT has created the S4 package as the latest upgrade to a range of Audi models. These include the A1 Sportback and the SQ8 luxury barge.