A businessman and part-time racer, Piotti achieved minor success in sports cars, including a class win in the 1952 Tour of Sicily in an OSCA, third place in a rather weak Targa Florio with a Lancia in 1954 and a win in the Hyères 12 Hours the same year in a Ferrari with Trintignant.
He made his Formula 1 debut in 1955, taking seventh place in the Syracuse GP in a works Maserati 250F, before purchasing a car for the 1956 season, in which he proved hopelessly slow, especially in the Argentine GP where he continually balked faster cars, eventually colliding with Collins Ferrari.
Piotti plodded through the 1957 season with the Maserati, and after finding little success in an OSCA in 1958 wisely returned to a more sedate occupation.