We’ve shown you the upcoming 2013 BMW 6-Series GT sports sedan before, but this time, our spy photographers spotted a prototype wearing the firm’s M Sport styling package.

If you’re familiar with the M division’s packages, then you won’t be surprised to learn that the styling differences between the standard and M Sport models concern the new front bumper with larger air vents, a showdown line treatment for the windows, a revised rear bumper that makes space for the new exhaust outlets.

The larger M-style alloy wheels shod in wider performance tires, round off the exterior updates on the four-door version of the 6-Series.

Also expect to see a lowered sports suspension and a raft of M-specific interior bits such as a leather-trimmed steering wheel, M-badged shifter and door sills, sport seats and new interior trim work.

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