It wasn’t so long ago that a brand new M5 had 500bhp. With the ACS2 Sport, we’re talking about a car not one class below that benchmark but two. And with 480lb ft, Schnitzer's tuned straight six also makes a fifth more torque than the high-revving V10 in the E60 M5.
Does it feel like a car that should accelerate to 100mph in around eight seconds? Not at first, although you can't really accuse the body of writing cheques the powertrain doesn't cash. The ACS2 is freakishly quick in a straight line, although as with the donor car, the engine’s delivery is now so linear that it all seems less dramatic than it might. The engine note – deeper, more booming, louder but more nasal than before – is also still a bit uniform, although it fires the car to 150mph on the autobahn without hesitation. Is this a 200mph M2? With enough space, maybe.
The way this car handles matters more. The factory M2 Competition offers a terrific base for changes, with rose joints in the rear suspension helping to control the original M2's occasionally unsettled tail. The things you really notice are that suspension travel seems to have halved and the centre of gravity has dropped. It's still no Porsche Cayman GTS, but compared with the M2 Competition, the Schnitzer's character is now fractionally more that of a purpose-built sports car than a quick coupé honed to an impressive degree. In a word, it's tauter.
Feeding into this is the fact this particular car is currently set up for track days, albeit ones you might drive to and from. The dampers are therefore quite a bit stiffer than you'd normally choose for pure road use and there's a greater degree of negative camber at the front axle. The result is two-fold: the car's steering response is more resistive than you're expecting but joyously sharp and precise, and the ride quality on less than decently smooth roads is shockingly bad. You can usually cure the latter either with excessive speed, at which point the dampers begin to flow along nicely, but that won't help you at lower speeds. With the dampers dialled down a touch and on the standard 19in wheels, the ACS2 would most likely ride as serenely as Schnitzer's cars are famed for, but as it is, the chassis chews on potted roads with far too much enthusiasm.
Find a good surface and the ACS2 Sport can show genuine brilliance. It communicates grip levels better than the standard car and resists understeer for longer. It'll still slip into big slides with ridiculous ease and maintain them with excellent yaw damping and effortless balance – to such an extent that the steering tracks the trajectory of the front wheels almost unassisted. The decision to stick the same 265-section rear tyres was sensible of Schnitzer, because going much larger could well have killed the car's playfulness. As it is, the ACS2 Sport can be stroked into oversteer with surprising delicacy.