That carbon fibre wing at the rear deserves some attention.

AC Schnitzer has done a lot of things with BMWs, primarily making the Bavarian cars more than what they already are. The German aftermarket gurus have already tuned the sporty X2 into a more capable athlete, as well as adding more aggressive cues to the 8 Series Coupe. They even turned the BMW i8 into an exciting machine that's meant to police the road.

This time, the German tuner turned its sights to the X4. The second Sports Activity Coupe in line gets bold upgrades inside and out in addition to more oomph to its power plant options.

Gallery: BMW X4 by AC Schnitzer

To increase the car's aesthetics and performance, AC Schnitzer added a few elements onto the X4's exterior design. First and foremost, the BMW X4 gets a front spoiler, rear roof spoiler, rear spoiler, and carbon fibre rear wing for cars that are meant for export. It also gets an AC Schnitzer-branded rear skirt protection foil.

Among the most notable upgrades are the set of wheel choices that comes with the AC Schnitzer X4. The choices are the following: 19-inch AC1 two-tone or anthracite alloy wheels; 20-inch AC1 two-tone or anthracite alloy wheels; 20-inch AC1 two-tone or anthracite alloy wheels with different widths; and the ultimate 22-inch AC2 two-tone or anthracite/black alloy wheels.

The tuned X4 is also noticeably lower in profile by 0.8 to 1.0 inches thanks to the AC Schnitzer suspension spring kit.

Interior, on the other hand, has been upgraded as well with aluminium pedals, footrest, keyholder, and the Black Line aluminium cover for the iDrive Controller.

Under the bonnet, the AC Schnitzer X4 xDrive30d gets upgraded from 265 bhp to 315 bhp (for export). The X4 xDriveM40d, on the other hand, gets an increase in performance from 326 bhp to 380 bhp.