Does Finke understand, to begin with, why early efforts at asymmetrical EV drivelines have left some of us a little unexcited at the potential of the tech? “I think so,” he says with a wry smile. “With the technology as it is, you really need to test it in very low-grip conditions like we have here to fully appreciate what it can do. On dry asphalt, the gains are a little harder to perceive, especially in an SUV like the E-tron. But they are there.
It’s time to press the reset button on my impressions, then. As a canvas on which to find out what the E-tron S Sportback’s tri-motor set-up can do on snow and ice, it’s a handling course carved out mostly in the image of the Nürburgring Grand Prix circuit that we have the run of. Other parts offer drift circles, slalom sections and longer, arcing, consistent-radius switchback bends that are ideal for testing lateral weight transfer.
The E-tron S Sportback’s handling does beat back my cynicism a little here. Early laps with the car set in its milder everyday driving modes and the electronic stability control fully active prove how benign and easy to drive it can be, even in tough conditions. It’s running on winter tyres with spikes, but it doesn’t struggle to maintain fairly committed speeds or to follow almost any cornering line you adopt on a surface on which you struggle to even walk without slipping over.
Here, says Finke, the car is biasing much more torque to the rear axle by default – but it’s also reading steering angle, yaw rate and lateral load all the time and working the outside rear wheel much harder than the inside one when it thinks you want the chassis to rotate. And when it does that, it’s manipulating the cornering attitude of a big, tall and heavy car really smartly and effectively
“If you turn in and accelerate at the same time, the software model sends all of the torque to the outside rear wheel, and it can do that instantly – much more quickly than any clever mechanical differential could,” says Finke. “Twin independent rear motors are a really elegant solution for this. We would have liked to use them in the E-tron GT [Audi’s electric sports saloon], but they couldn’t be packaged along with the four-wheel steering.