But it's good to see the dedication, and in its stiffest and lowest form it helps 3,900 pounds of car whip through bends flat and true. Push it too hard, especially on a damp road, and it will tip into benign understeer as the 20-inch wheels, wrapped in Continental SportContact2 rubber, divvy up the available grip - but there's also that reassuring front end pull that means you can go in too fast, way too fast, and the car will find a way through. It will never have the drama of rear-wheel drive, but it is supremely quick.
With all this extra power, extra braking is essential, and ABT has gone whole hog with 380mm steel discs and six-piston calipers at the front that wouldn't look out of place on a top-end supercar. With the reduced pitch from the stiffer suspension and the grip from the rubber these anchors actuating almost feels like hitting a wall, even in the wet, and it's almost too sporting for a car this size, especially when it retains all the creature comforts inside and just a splash of carbon-fiber and aluminum trim to mark it apart from the standard business coupe that spends its life pounding the left-lane of the autobahn. Of course there are also the retina-searing seats, but that's Audi's work and not ABT's.
And that's where the journey ends, as we head back to the factory on the derestricted, arrow-straight German expressway, with the LEDs and headlights ablaze, 160 mph on the clock and the whole world jumping out of this venomous creature's way as it howls down the outside lane.
At least we had the decency to warn them, though. In the color-coded, toned-down customer cars, or in the upcoming RS5, they'll never even see this fatal bite coming.
ABT Sportline AS5-R
Longitudinal front engine, all-wheel drive
4.2-liter V8, dohc, 32-valve.
Lysholm supercharger, ABT software
Six-speed manual, ABT short shifter
Six-piston calipers with 380mm ventilated steel rotors (f)
Wheels and Tires
ABT BR Sport, 9.0x20
Continental SportContact2, 265/30/20
Peak Power: 503 hp @ 6800 rpm
Peak Torque: 457 lb-ft @ 3500 rpm
0-62 mph: 4.3 sec.
Top Speed: 181 mph