Ahead of next year’s highly-anticipated unveiling, BMW provided a preview of its upcoming M4 – by outfitting the 4-Series Coupe with the M4′s M Performance parts. The result: an automobile significantly more aggressive and powerful than the original 4-Series Concept. A new body kit provides a modified front bumper with a carbon fiber splitter and enlarged air ducts, a new rear bumper with both air extraction ducts and an included diffuser, new side sills, carbon fiber mirror housing, xenon LED headlamps, 20″ alloy wheels, and blackened chrome trim throughout the exterior. Underneath the hood, the M Performance package boosts engine performance for each type of available set-up: the 4-cylinder, 2.0-liter turbocharged diesel 420d engine is capable of 195 bhp and 309 lb-ft of torque; the 4-cylinder, 2.0-liter turbocharged gasoline engine of the 428i is capable of 269 bhp and 287 lb-ft of torque; and the 435i’s 6-cylinder, 3.0-liter turbocharged gasoline engine boasts 336 bhp and 332 lb-ft of torque. Final details include an updated exhaust, tweaked software, and an optional limited-slip differential. Stay tuned for a look at the BMW M4 itself, which is expected to be unveiled at the Detroit Motor Show come January 2014.