With the memory still alive of the only edition of the 800 kg world championship racers in 1953 that saw the triumph of the late Mario Verga, the UIM, after three years of silence, proposes this title again with its assignment scheduled on the dispute of three heats on the same day in the international meeting organized by MILA on the waters of Ceresio in Campione d'Italia. Much anticipation, for a challenge that sees our pilots Ezio Selva, Carlo Casalini, Liborio and Flavio Guidotti, competing against a first-rate foreign participation. The German Christoph Von Mayemburg and the French Luois Delacour and Maurice Bauchet are joined by the fearsome American Sam Du Pont.

In a challenge expected to have strong content, the comparison between the powerful Timossi-Alfa Romeo 159 of Selva and the Lauterbach-Chevrolet of Du Pont, unfortunately fails in the initial stages of the first heat, when the American, suffering an incredible rupture of the fuel tank on his hull, is forced to retire. Ezio Selva, after the fast start of Flavio Guidotti, in the lead of the race but then retired, dominates the first heat leaving in his wake the Timossi-Maserati of Liborio Guidotti and Von Mayemburg. In the interval between the first and second heats a great gesture of fair play is exhibited by Selva in putting his mechanic Merlini at the disposal of Du Pont to help him repair the damage to the tank, allowing the unfortunate driver to return to the race in the other two races. Since this is a championship in which the victory is counted with the sum of the times achieved in the three heats, it seems obvious that the world championship for Du Pont is compromised. So, even in the second test against Selva and his red Moschettiere , there was little to do: the driver clearly prevailed over Liborio Guidotti and the returning Du Pont.

The latter's much feared Lauterbach-Chevrolet does not reveal, at least in the race for the Italian Champion, its much-touted potential. Ezio Selva's dominance is such even in the last heat, where Liborio Guidotti retires, with Du Pont and Von Mayemburg in second and third place. With this world success, Ezio Selva enters fully into the elite of the great international inboard racing. With a constant performance and a pinch of good luck, the German Von Mayemburg manages to finish in the final classification behind the winner Selva, preceding, with his Streves-Jaguar hull, also the powerful Timossi-Maserati of Liborio Guidotti and the Lauterbach-Chevrolet of Du Pont.
In a day that is certainly not lucky for the Guidotti clan, the only satisfaction comes from the fastest lap of the entire championship recorded by Flavio Guidotti during the only three laps completed during the first heat with over 121 km/h. The performances of the other Italian, Casalini, and of the two transalpines Delacour and Bauchet were also disappointing, although they were classified albeit with huge gaps.

The final ranking (only the first four classified) is as follows:
1st Ezio Selva on Timossi-Alfa Romeo 159
2nd Christoph Von Mayemburg on Sreves-Jaguar
3rd Liborio Guidotti on Timossi-Maserati
4th Sam Du Pont on Lauterbach-Chevrolet

In 1956 the Italian 2500 cc inboard racing championship was established. The class, identified by the acronym Z, would have a great success in the years to follow. In its first edition the tricolor was won by Giorgio Guidotti, another young scion of Italian motorboating, together with his brother Flavio. On the measured base of Sarnico the great performance of the driver Dino Sestini stands out who, aboard his 3-point Tamiri 3° , built by Timossi and powered by an Alfa Romeo 159, established the new world speed record for racers up to 500 kilos with an hourly average of 206.780 km.