The still-fresh CLS 63 four door Coupe and Shooting Brake styling will remain untouched, but the AMG 5.5 litre twin-turbo V8 will be boosted to 410kW and 720Nm for 2013.
The tweaks don't end there, with the current Performance Package renamed ‘S-Model’ and delivering a hearty 430kW/800Nm.
In left-hand-drive markets, a 4Matic all-wheel drivetrain will become an option for the first time, with a performance-focused 33:67 front/rear torque split and torque vectoring capability.
All models continue with AMG Ride Control adaptive suspension, while the S-Model scores a locking rear differential and optional 402mm ceramic composite brakes.
Mercedes claims E 63-identical 0-100km/h performance figures for the new CLS 63, which means 4.2 seconds for the regular 'Coupe', 3.7 seconds with the 4Matic drivetrain, and a Ferrari Enzo-matching 3.6 seconds for the S-Model with 4Matic.
Shooting Brake variants are a claimed 0.1 second slower for each variant.
The upgraded CLS 63 SMG is set to arrive in international showrooms from April, with S-Model and 4Matic variants due in June.