Career
His most successful period was from 1977 till 1990 when he partnered Finnish driver Hannu Mikkola, first in the Ford Escort RS1600, later moving on to the RS1800. He also navigated Mikkola to his world title in 1983, again in the venerable Quattro. The pair were always contenders on any event they entered during their thirteen years together.
In 1988 when Mikkola switched to the Mazda team, Hertz stayed with Audi, teaming up with German driver Armin Schwarz.