In 1980, Audi released the Quattro, a four-wheel drive (4WD) turbocharged car that went on to win rallies and races worldwide. It is considered one of the most significant rally cars of all time, because it was one of the first to take advantage of the then-recently changed rules which allowed the use of four-wheel drive in competition racing. Many critics doubted the viability of four-wheel drive racers, thinking them to be too heavy and complex, yet the Quattro was to become a successful car. Leading its first rally it went off the road, however the rally world had been served notice 4WD was the future. The Quattro went on to achieve much success in the World Rally Championship. It won the 1983 (Hannu Mikkola) and the 1984 (Stig Blomqvist) drivers' titles, and brought Audi the manufacturers' title in 1982 and 1984.