The German tuners from Vath have got you covered in case you consider that a stock Mercedes CLS63 AMG is not quite the beast you expected to be.
This new performance upgrade which they call the C218 costs 12,800 Euro and consists of engine electronics fine tuning, an optimised air cooling system and a sports exhaust system with stainless steel catalysts plus middle and tail mufflers.
Due to this tweaks the VATH C218 Mercedes CLS63 AMG is now  capable of outputting 660 HP (484 kW) and 960 Nm of torque, figures that will get translate into unique thrills when accelerating from 0 to 100 Km/h (62 mph), as the car will only require 3.9 seconds to do that.
The 0 to 200 Km/h (124 mph) sprint time is 12 seconds flat while the new top speed is 325 Km/h.  
Other adjustments performed on the VATH C218 Mercedes CLS63 AMG include the lowered suspension which costs 980 Euro, the upgraded brakes priced at 590 Euro plus a series of visuals like the new airflow front spoiler (1,490 Euro), the trunk lid lip (1,480 Euro) and the custom rear diffuser priced at 1,490 Euro.
The VATH C218 Mercedes CLS63 AMG sits on 3-piece 20 inch forged wheels wrapped in performance tires size 265/30ZR20 at the front and 305/25ZR20 at the rear. The wheel and tire combination will set you further back with 6,337 Euro.    

Source: Vath