The new 850 6.0 Biturbo is seen by Brabus as a replacement for the 800 E V12 but, instead of its predecessor's 12-cylinder engine, the new car is powered a twin-turbo V8.
Based on the 5.5-litre unit used in the E63 AMG, the 850's engine has been bored and stroked to 5.9 litres. Equipped with two Brabus turbochargers the 5.9-litre V8 churns out 625kW or 850 metric horsepower, hence the name. Brabus claims that the highly modified V8 can produce 1450Nm of torque, but has been limited to just 1150Nm in order to preserve the rest of the drivetrain.
A seven-speed dual-clutch automated transmission sends all that "Sturm und Drang" to either the rear wheels or all four. Rear-wheel drive 850s can complete the 0-100km/h standard in 3.7 seconds, while all-wheel drive versions take only 3.1 seconds to do the same dash. Top speed is electronically limited to between 300km/h and 350km/h depending on the owner's choice of tyres and final drive ratio.
In comparison the E63 AMG S-Model offers only 430kW/800Nm from its 5.5-litre twin-turbocharged V8. This allows the big sedan to run the 0-100km/h sprint in 4.1 seconds in rear-wheel drive form and in 3.6 seconds when fitted with all-wheel drive.
The 850 6.0 Biturbo is available as either a sedan or wagon; both versions are fitted with a carbonfibre aero kit as standard. Brabus offers a selection of one-piece wheels for prospective owners to choose from and these can be clad in rubber from either Continental, Pirelli or Yokohama.
On the inside you'll find Brabus-branded aluminium shift paddles and pedals, while every conceivable surface is trimmed in leather that can be coloured to taste.
The 850 6.0 Biturbo can be purchased outright or components added piecemeal to any current model E63 AMG.
For those with slightly shallower wallets or tamer tastes Brabus will also offer modified versions of the E63 AMG's engine that do without the 850's displacement increase. These are available in three states of tune: 456kW, 478kW and 537kW.