Power for the big top-shelf CLS is provided by AMG's new 5.5 litre bi-turbo V8 engine, delivering 386kW and 700Nm of torque into the hands of its owners - and that's 8kW and 70Nm more than the outgoing 6.2 litre V8 provided.
The new V8's top power is available at 4400rpm, with maximum twist coming online between 2000rpm and 4500rpm.
Power is sent to the rear wheels through Mercedes' seven-speed multi-clutch transmission, and fuel economy is rated (in the US market) at around 14 l/100km in the city and 11 l/100km on the highway - an overall improvement of about 33 percent.
The 0-100km/h sprint is covered in 4.4 seconds, with a top speed of 250km/h.
The CLS 63 benefits from the same mechanical tweaks as its siblings in the AMG stable, including revised suspension, braking and aero components.
For those needing a little more, an even more powerful version of the engine is also on offer, boosting numbers to 410kW and 800Nm of torque thanks to the AMG Performance Package.
The AMG Performance Package also offers a carbon fibre AMG boot-lid spoiler, red-painted brake calipers and an AMG Performance steering wheel with Alcantara inserts.
Other optional AMG Performance Studio features include AMG Ride Control suspension, forged AMG five-twin-spoke light-alloy wheels, AMG rear axle locking differential, AMG ceramic composite brakes, AMG exterior carbon package, AMG carbon fibre cabin and piano black cabin trim, and illuminated AMG door sill panels.
2011 Mercedes-Benz CLS 63 AMG - $263,500 (plus on-road costs).