A Military Contract and Rally Racing Led Audi to Revolutionize All-Wheel Drive

[Steve Q]

The inspiration for the seminal Quattro came from a four-wheel-drive off-roader Audi built for the German army. 

I should confess: I’m a massive motorsports nerd. I find it addicting to watch the best racing drivers in the world go head to head. But aside from the spectacle, motorsport is intriguing for how it’s essentially a proving ground for automotive engineering and tech developments, some of which then trickle down to road-legal vehicles. Such was the case with all-wheel drive, a story that involves the Audi Quattro—and one of the best rallying battles in history. 

It began in 1977, when Audi was tasked with building an all-terrain vehicle for the German military. Referred to as the Volkswagen Iltis, it featured a four-wheel-drive system built from the underpinnings of the Audi 100 sedan. After testing the machine in the depths of winter on an off-road test track, the German automaker realized that the Iltis could jostle through the terrain much faster than any of its much more powerful front-wheel-drive sedans. 

 

Jörg Bensinger, one of the engineers who had worked on the Iltis, figured that having four driven wheels could be a great catalyst to fulfill Audi’s goal of building sophisticated road cars that could be modified to go rallying. He pitched the idea to the company’s head of research and development, Ferdinand Piëch, who agreed to the idea. Having two driven axles wasn’t necessarily a new idea, but it had never been applied to a small vehicle like a sedan. In doing so, Audi created what we now refer to as all-wheel drive. 

Instead of a clunky transfer case, which wouldn’t really fit within the small confines of a passenger car, the first proper Audi Quattro utilized a center differential with a clutch pack to split the torque between the front and rear wheels. The central diff was a much neater solution that the driver could manually lock with a switch in the cabin, allowing for a 50/50 torque split between the front and rear wheels. 

Later versions of the Quattro featured a much more advanced Torsen diff that could sense which wheels were losing traction and alter the torque split to optimize forward drive. The clever innovation that made the system possible was utilizing a hollow output shaft coming from the transmission, which allowed Audi to run another shaft straight through the middle of it to drive the front wheels. 

The culmination of Audi’s efforts was the Ur Quattro, which made its debut at the 1980 Geneva Motorshow. “Ur” isn’t a misprint; it’s German for “original.” This Ur Quattro was one of the most advanced parts-bin cars that the automotive industry had ever seen. Its state-of-the-art AWD system allowed drivers to enjoy the inherent traction advantages on pavement. This was unheard of, as conventional four-wheel-drive systems are only usable off road. 

Shortly thereafter, the brand started Audi Sport, its racing division that would build the Quattro rally car, which was more powerful and sported a roll cage. Proving the capabilities of permanent AWD, the first Quattro race car went on to finish first in the 1981 Algarve rally by 30 minutes—but couldn’t officially be declared the winner, as it hadn’t been homologated yet. (The World Rally Championship, or WRC, requires each manufacturer to build 400 individual road-legal vehicles based on the race car to be eligible for competition.) Audi would go on to win the championship in 1982, a victory that would be overshadowed in 1983 thanks to its titanic battle with Lancia and the rear-wheel-drive 037.

Audi was a determined team (funded by Volkswagen), with Roland Gumpert at the helm and one of the best driver lineups that the WRC had ever seen. Meanwhile, Lancia was an Italian team run on a tight budget by Cesare Fiorio, who was famously a bit of a playboy who also had a vested interest in powerboat racing. Still, Lancia’s driver lineup, led by Walter Rohl, was equally sublime. While Rohl was one of the most skilled drivers to ever grace the WRC, he didn’t want to compete in all of the rounds of the championship, and also didn’t want to be world champion—making the Italian team’s campaign all the more difficult. 

While Audi may have had an advantage on pace, the Italians at Lancia had been rallying for decades, and they were infamously creative in their interpretation of the rules. One of my favorite and most talked-about “cheats” that they employed in the Monte Carlo rally that year was swapping the studded winter tires mid-stage for standard rally tires that would better suit the upcoming conditions. There was nothing in the rulebook that said you could do it, but also nothing that said you couldn’t. At the end of the season, Lancia won the championship, making it the last team to win the WRC outright with a rear-wheel-drive vehicle. 

Audi ported the brilliance of the Quattro into other road vehicles in its lineup. And in the years that followed, automakers around the world caught on to the benefits of the all-wheel-drive system that started it all.

https://www.popularmechanics.com/cars/car-technology/a39691216/audi-quattro-all-wheel-drive/