The dynamic security we expect from Audi's RS models has been joined by a playful side thanks to a high-tech differential. I did not see this coming. I'm standing next to a tiny track tucked into a narrow valley in the Austrian Alps about an hour outside of Salzburg. Hemmed in by sheer rock walls and snow-dusted peaks the shape of bent arrowheads, this track probably has the best view of any in the world. It looks like an AI render, but everyone in attendance seems to have the correct number of fingers, so apparently the scene is real.
It's only because Austria is absolutely filthy with such beauty that a track could ever be situated here. There is a fleet of four new Audi RS5 sedans parked at the side of the track. They are painted a shade of green that Audi calls Bedford and that I would describe as either tasteful or somber, depending on my mood. As I soak in the view and wait my turn to take the 630-hp plug-in hybrid RS5 out on the track, my mood is decidedly positive.
If the location is difficult to believe, so is the action on the track. You see, out there on this hilly little circuit (with the deeply unsexy name ÖAMTC Driving Technique and Experience Center) are a couple of Audis drifting around, squawking as they hang their tails out. Audis are nose-heavy, though, right? Everyone knows they understeer when pushed, right? This display wouldn't be such a surprise if it were a pro driving instructor or an Audi dynamics engineer making the heavy sports sedan dance.
View Price on AmazonBut it's also journalists out there. Journalists who have essentially had no previous exposure to the car, have never seen the track, and have only three short laps each before their time is up. What is going on? Well, the RS5 is . . . weird. First, it looks a long way from Audis of yore, with their sheer, sparsely adorned body panels. This sports sedan (or five-door hatchback, or, as Audi calls it, Sportback) bulges and flares in a most immodest and complicated way. It aims to look angry.
Also, this RS5 is a plug-in hybrid, the first in the performance subbrand's history. It carries a hefty lithium-ion battery back with 22 kWh of usable capacity over the rear axle, stealing some of the cargo area's depth. Because the RS5 won't make it to dealers in North America until at least 2027, there is no EPA estimated EV range, but based on the WLTP European testing standard, the car should have about 35 miles of pure electric range, maybe more. Whatever the number, it will be more than the nominal EV range of early luxury plug-ins.
But the one element that most defines the RS5's strangeness is mounted under that high-voltage battery. It is the thing that allowed those green sedans to drift around the track with such apparent ease. It is the part of the car that the company seems most proud of. And it is what prevents the very heavy RS5 from feeling ponderous and inert. It is the Dynamic Torque Control unit, otherwise known as a torque-vectoring differential.
This large box of complexity mounted between the rear wheels is different than your typical e-diff. Developed jointly by Audi and Borg Warner, this electromechanical arrangement does more than provide stability or prevent the inside wheel from spinning during cornering by apportioning torque across the rear axle. Composed of an open differential, a couple of planetary gear sets, and a water-cooled electric motor that can produce 11 hp and 30 lb-ft, Dynamic Torque Control is a much brawnier system than those which operate exclusively with engine-derived power.
It can transfer torque left or right in just 15 milliseconds and, thanks to the multiplication effect provided by gearing, up to 1475 lb-ft can move across the rear axle to overspeed an outside wheel momentarily and dramatically impact handling balance, Audi says. And unlike most torque-vectoring solutions, Audi's system can perform its magic even while the powertrain is contributing no real power, as when the car is coasting or braking. It is, in effect, a re
Source: roadandtrack.com
