Brabus’s skilled engineers have developed two new power upgrades for the AWD versions Mercedes CL 500 and S 500 4MATIC equipped with the 4.7-litre 8-cylinder twin-turbo engine rated at 435 hp (429 bhp) / 320 kW and 700 Nm (516 lb-ft) of peak torque as standard.
This first power upgrade is called the Brabus B50 – 490 and it consists of the tuner’s plug-and-play PowerXtra module that calibrates the engine’s electronics and optimizes the ignition, injection and the electronic boost pressure control. Thanks to this kit the 4.7-litre engine mentioned above will produce an additional 55 HP for a total of 490 hp (482 bhp) / 360 kW and 780 Nm (575 lb-ft) of torque.
The second performance kit is the Brabus B50 – 520 PowerXtra which features an additional intercooler and dials up performance to 520 hp (512 bhp) / 382 kW at 5,250 rpm and 820 Nm (604 lb-ft) of torque between 1,800 and 3,500 rpm.
These new figures will enable the CL 500 4MATIC BlueEFFICIENCY to accelerate from 0 to 100 Km/h (62 mph) in 4.5 seconds and reach a top speed of 300 Km/h (186 mph). This new top speed requires the installation of a new speedometer from Brabus that has a 360-km/h (220-mph) dial.
Performance figures for the S 500 model are at the same level, and apart from these two engine upgrades, Brabus is also offering a stainless-steel sport exhaust system, custom tailored wheels ranging from 18 to 22 inches in diameter, a lowered suspension and numerous styling tweaks at both the exterior and interior.     
Brabus will showcase these two upgrades between November 26 through December 4 at the 2011 ESSEN MOTOR SHOW.

Source: BRABUS