Mercedes-AMG has added another variant to its GT range with the debut of the GT C in Detroit. The coupe follows on the GT C Roadster that premiered in Paris last year, and brings the road-going C190 AMG GT family line-up to six (GT, GT Roadster, GT S, GT C, GT C Roadster and GT R). Seven in completion, if you count the GT3 racer.

Positioned between the AMG GT S and AMG GT R models, the GT C will initially be available as a special Edition 50 model to mark the 50th anniversary of AMG this year. The Edition 50 will be available in two exclusive special paint finishes, designo graphite grey magno and designo cashmere white magno.

Styling elements include black chrome highlights on the side skirt trim, front splitter, the trim strips in the grille air inlets, fins on the side air outlets in the front wings, the rear diffuser and exhaust tailpipe trims.

The interior, meanwhile, gets a black and silver scheme and comes standard with an AMG Interior Night package. Dressed with exclusive nappa leather in silver pearl/black with grey diamond-patterned contrasting topstitching, the car also gets “Edition” lettering on the steering wheel bezel and GT Edition 50 embossed on the front seat head restraints as well as silver seat belts.

Like the Roadster, the GT C borrows numerous technical highlights from the range topping GT R. Identifiable by its broad, muscular rear end and large wheels, the car also features a wider rear track and active rear axle steering – its 57 mm wider at the rear than the base GT.

As with the GT C Roadster, the 4.0 litre V8 biturbo M178 mill offers 549 hp (or 557 in PS) at 5,750 to 6,750 rpm and 680 Nm at 1,900 to 5,500 rpm. Performance numbers are identical as well, with a 0-100 km/h time of 3.7 seconds and a 317 km/h top speed (that’s one km/h more than the open top, if you want to be precise about it).

As standard, the car comes fitted with an active rear-axle steering from the AMG GT R and an electronically-controlled rear-axle limited-slip differential, which is integrated into the compact transmission housing. There’s also AMG Ride Control sports suspension, which features infinitely variable, adaptive adjustable damping.

In Detroit, the automaker also revealed the updated GT and GT S, which now wear the distinctive AMG Panamericana vertical grille. There’s also a new front apron, which further emphasises the width of the car, and larger outer air inlets for improved cooling to the engine. All the GT variants now feature the Airpanel active air management system as standard.

Outputs have also been restructured, with the base GT now offering 469 hp and 630 Nm (13 hp and 30 Nm more than on the initial car), while the 2017 GT S now puts out 514 hp and 670 Nm, an increase of 11 hp and 20 Nm from that seen previously.

In addition to the improved active aerodynamics, higher output/torque and active rear-axle steering, the update for the GT also includes significant additions to the scope of equipment.

A host of new optional extras are available, including an AMG Exterior Chrome package with trim in high-gloss chrome and an AMG Interior Night package from the GT R. Other items include new wheel choices and an AMG Dynamic Plus package for the base GT as well as an active rear-axle steering for the GT S.