 Two years later, Audi, unveiled the second duo generation, the Audi 100 Duo – likewise based on the Audi 100 Avant quattro.Once again, this featured an electric motor, a three-phase machine, driving the rear roadwheels.This time, however, the rear wheels were additionally powered via the Torsen centre differential from the main engine compartment, which housed a 2.0-litre four-cylinder engine.