While there’s no shortage of tuners putting wrenches to factory-fresh hardware in search of performance, it takes a special kind of lunacy to crack open a gleaming 6.0-liter V-12 for a minor displacement increase of 0.3 liters. In this case, the lunatic is German tuner Brabus, and the engine in question resides between the fenders of the Mercedes-AMG S65 coupe. Not content with the twelve-cylinder?s silky-smooth 661 factory-supplied ponies, the masterminds at Brabus set about poking around the engine’s nether regions.
Twelve forged pistons were required to match the scantly increased cylinder bores, and while they were inside, Brabus thought it best to fit specially balanced connecting rods and a billet crankshaft with a longer stroke. Once the internals were up to snuff, Brabus tossed the factory turbos, replacing them with its own units with larger compressors and turbines. There’s a custom intake that uses heat-reflecting sheathing to keep intake temps down, while special mapping ensures that fuel delivery and ignition keep things on the same page, combustively speaking. Fitting the new turbos required modifying the exhaust manifolds, so Brabus went ahead and mounted larger 3.1-inch downpipes and a stainless-steel exhaust with ceramic-coated satin-black tailpipes. Naturally, the system features active butterfly valves to control the exhaust tone from the driver’s seat. (If this sounds a tad familiar, it’s probably because you’...