As I'm sure many CLS 55 AMG owners can attest to, one of the most common problems when admiring the four-door coupes impeccable lines is whether or not to add to the vehicle's already mesmerizing appearance.

Although I tend to be more of the standard AMG type myself, many opt for a far less traditional approach, and it is to this crowd that ART offers their latest tuning package.

Titled the GTR, ART's latest tuning program spans the gamut of your beloved CLS, with modifications ranging from the engine and suspension all the way down to your door sills.

For starters, customers have the option of two enhanced engine packages. The first, titled the GTR560, ups the CLS' standard AMG V8 to 560hp/790Nm, enough to propel the GTR from 0-60 in 4.4 seconds.  If you're looking for something a little quicker, ART has obliged, also offering customers the GTR620 package.  The result is an increase in power to 620ps/890Nm, enough to propel your CLS from 0-60 in just 4 seconds.

In addition to the power enhancements, a number of performance enhancements have been added as well.  A new electronically adjustable ART suspension package widens the GTR's track by 70mm in the front and 80mm in the rear; 20" light alloy rims help keep the GTR's power planted firmly on the ground; and a new ART sport exhaust makes sure the GTR's growl is indicative of what's under the hood.

And finally, ART has addressed the vehicle's appearance. To help accommodate the GTR's wider track, ART has included new front and rear wings with wider sills, door applications on the rear doors, a new front and rear bumper, a new trunk lid, and a rear wing.  Inside, ART has added a number of aesthetic touches, a few of which include carbon fiber accents, leather and alcantara upholstery, and last but certainly not least, neon blue door sills.*

Whew.  That was a mouthful.

Believe it or not, there's a number of options I've failed to mention, but this should give you a pretty good idea of what ART can do for you and your CLS.  For more info, check out some pictures below (click to enlarge), and head over to ART Tuning's website to learn more about anything I've mentioned.

*Note:  Pole and strippers not included.