Quote Originally Posted by bearclaw View Post
The first double champion Walter Röhrl did it. He won in 1980 with fiat (fiat 131 abarth) and 1982 with opel (opel ascona 400).
You got that wrong. Kankkunen won with three manufacturers (1986 Peugeot, 1987/1991 Lancia, 1993 Toyota), but no one has managed multiple championships with two manufacturers. So you would need at least four titles in total, at least two with each manufacturer.