Campari's job eventually involved test driving factory cars and his skills and interest led to his participation in competitive hillclimbing events.

He repeated as champion at Mugello the next year and took third place at the Targa Florio but did not earn another major championship until he captured the French Grand Prix in 1924 when he was part of a powerful three-man Alfa Romeo team with Count Gastone Brilli-Peri and Antonio Ascari in the P2 cars designed by Vittorio Jano.

The following year he repeated as champion at the Mille Miglia and along with top drivers such as Malcolm Campbell and Rudolf Caracciola, he traveled to Ireland to compete in the inaugural Irish International Grand Prix at Phoenix Park in Dublin.

Run in front of more than 100,000 spectators, Campari was hit in the eye by a flying small rock but was successfully treated in hospital and the race was won by the Russian émigré, Boris Ivanowski.

After a sensational debut season, Nuvolari and Campari combined to win their first Italian Grand Prix, a victory that made them national heroes for taking the championship from the French who had won it for the past three years.