Group B homologation rules created a platform for manufacturers to develop and introduce daring new technologies.

No make encapsulated that ambition quite like Audi, which took the four-wheel-drive concept from the farmyard to the special stage, changing the sport of rallying forever and creating one of the most sought-after model ranges in automotive history.

Famed for its thrilling battles with close rival Lancia (and later, Peugeot), for the true petrolhead the definitive Group B rally car is the Audi quattro S1 E2.

Audi had already been entering successful Works quattros in Group IV before the FIA changed the homologation categories.

And while Group B regulations would eventually lead to incredible speeds and an unmanageable level of danger, they also drove automotive development.

While other manufacturers scrabbled to catch up—Lancia beginning development of its Delta S4 in 1983—it became clear that Audi had chosen the right development path, highlighted by dominant rally vic...