The performance division of Mercedes - AMG - is kicking off its 50th anniversary celebrations with the launch of a new GT C Coupe. Unveiled at the Detroit Auto show, the GT C will initially be available exclusively as a special ‘Edition 50’ model, with plenty of black chrome and unique paint finishes including graphite grey. Power comes from a 4.0-litre V8 engine delivering 557 horse power, which translates into a 0-62mph time of 3.7 seconds. Meanwhile, the Mercedes-AMG GT and GT S have also been facelifted and upgraded with even more power.