1980 Audi Quattro: All-Wheel Drive
Full-time all-wheel drive is an idea nearly as old as the car itself, but it was expensive and difficult to engineer well. A few AWD experiments, like the 1966 Jensen FF, made it to market, but the systems were all flawed in some way. Then in the late 1970s Audi began experimenting with all-wheel drive systems, and by 1981 had found exactly the right place for their advantages to be expressed: world rally racing. On the gravel and dirt of rallies, Audi's Quattro system was instantly impressive, even as teething problems were frustrating. But by 1982 the Audi Quattro was dominant, winning nine of the WRC events that year. Every other rally car was suddenly obsolete. Over time AWD has spread to the point where practically every manufacturer offers at least one production vehicle so equipped in their line.