The C-Class is Mercedes-AMG's best-selling model series, and now the firm has unveiled what it says is the sportiest C-Class ever. The C 63 Coupé can accelerate from 0-100 km/h in four seconds. That makes it faster than its predecessor, which held the crown of fastest C-Class ever.

The top speed of the new C 63 Coupé is electronically limited to 250 km/h (155 mph), or 290 km/h (180 mph) with the AMG Driver's Package. That speed is created by a 4-liter AMG V8 biturbo engine, which Mercedes-AMG says is the only engine of its type in the segment. It can kick out up to 375 kW (510 hp).

The modifications to the model include flared front and rear wheel arches, an increased track width and larger wheels. The flared arches make the car 64 mm (2.5 in) wider at the front and 66 mm (2.6 in) wider at the rear, which Mercedes-AMG says allows the car to hug the road better and give it a more muscular body shape.

The 7-speed sports transmission is said to change up and down gears significantly more quickly than the previous non-coupe version of the car, either automatically or manually via the flappy paddles. Mercedes-AMG says this is made possible by a sportier set-up of the engine and transmission parameters. There are four different transmission modes in total, ranging from an economical focus to a sporty focus.

The C 63 Coupé also has a redesigned suspension that provides better agility and the ability to corner at higher speeds. As with the transmission, the suspension can be adjusted for different levels of sportiness.

The Mercedes-AMG C 63 Coupé will premiere at the Frankfurt International Motor Show in September, before going on sale in markets around the world from March next year. There's currently no word on pricing.

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