To drift or not drift? That is the question.
Audi gave us a sneak peek of the 2022 RS3 sedan last week, but we can't talk about it until next month. What we can talk about is the new bit of tech it will use, called RS Torque Splitter. It'll be the first Audi to feature this specific system, though other VW Group vehicles use a similar but different arrangement.
"It was co-developed with the Golf R, but we have our specific setup. We have different camber, tires, a very distinct setup for the RS3. It has a different engine, different transmission, so a completely different feel," said Audi engineer Meic Diessner.
As the name implies, the system splits torque in the RS3, at the rear wheels. When you're at the limit, at the edge of grip in a corner, your inside wheels will start spinning first. That's because in a normal car the power is sent to the wheel with the least resistance, the least grip. And with the weight shifted outward in a turn, those inside wheels are the first to get loose. That means instead of 11s made from rubber on the pavement with both wheels spinning, you'll just leave 1s. This new system feeds power to that inside rear wheel when cornering, to adjust the car's direction towards the apex of the turn, where you want it to go.
"This results in optimal stability and maximum agility - especially when cornering at high speeds. When driving on closed roads, the torque splitter enables controlled drifts by applying all of the engine power to just one of the rear wheels - up to a maximum of (redacted) newton meters of torque," says Audi.
As the power goes rearward to the rear axle - although with Audi's quattro AWD system some is always going to the front - it runs into two multiple-disc clutches on the back axle, each with its own control unit. Those units use the wheel speeds, longitudinal and lateral acceleration, the steering angle, the position of the gas pedal, the selected gear and yaw angle to choose how much power to send to each side.
Above that, the brain of the entire system is now called the modular vehicle dynamics controller or mVDC. That system looks at the two torque splitter control units, the adaptive dampers and the torque to the wheels. Audi says the system is used on the A3 and S3, but is sped up in the RS3. "All in all, it increases the agility of the entire vehicle, especially on dynamic stretches of road," said Audi.
"All-wheel drive cars have great tracking stability," said Frank Stippler, Audi test engineer, "but they tend to understeer at the very upper limits. We were looking for a solution that would minimize that behavior. The torque splitter distributes more weight onto the rear axle. With it, the car develops a driving dynamic that oversteers. And that's where the Audi drive select system comes in, which helps meter that tendency based on use, road conditions and individual preferences."
The Audi drive modes will have an affect on how the RS Torque Splitter acts. The new RS3 will get seven modes, with five characteristic formulas including Comfort/Efficiency, Auto, Dynamic, RS Performance, and RS Torque Rear. That last one is obvisouly for drifting "on a closed course," but as you move from Comfort/Efficiency towards the RS modes, that RS Torque Splitter gets more active. The system also reacts to the weather.
"It recognizes, for example, if the road is wet or dry. So, the driver doesn't have to change the mode," said Diessner. "That means that the car automatically reacts differently in RS Performance mode if the road is wet than it would when it is dry. The driver also benefits from the variability of the RS Torque Splitter all the way to the top speed."
The splitter or, "ze RS Torque Splittah" in German, was tested in two self-contained runs of about 4,000 miles a piece. It was also thrashed mercilessly on the Nordschleife by both Diessner and Stippler, so we're assuming the tech is ready for prime time. We'll see the official reveal on July 19, and hopefully we'll test drive it soon after.