Record-setting 1953 Timossi-Ferrari V12 hydroplane is as rare as it gets

Luigino "Gigi" Barp, the head of technical service at Ferrari Classiche, the company's restoration and certification division, says it is impossible to put a value on the 1953 Timossi-Ferrari Arno XI hydroplane racing boat. It's a one-of-a-kind piece with a one-of-a-kind engine that was specially designed to beat and set the world speed record on water. With Achille Castoldi behind the wheel, it achieved that goal back in 1953. In 2019, after a restoration and some time at the Ferrari Museum, it's for sale on DuPont Registry. 

Although numerous Ferrari automobiles have set many records and earned countless first-place finishes on land, there is only one world-record-holding Ferrari-powered boat. The details and timelines of how it all came together are a bit murky, depending on the source, but it all centers around Castoldi, a world-class boat racer from Italy.

According to RM Sotheby's, Castoldi had success with Alfa Romeo in lower-weight-class racing in the '40s before deciding he wanted to set the water speed record in the 800-kilogram class. Castoldi was reportedly friends with people at Ferrari, and he was fortunate enough to secure a Tipo 375 V12 engine for a three-point hydroplane built at Cantieri Timossi boatyard in Italy. That's the same engine Ferrari was using for its F1 Grand Prix cars of the time.

After realizing the engine was still not powerful enough in its original form, Castoldi reportedly worked with Scuderia Ferrari’s chief race engineer Stefano Meazza to up the power. The engine, which started at roughly 385 horsepower, reportedly gained two superchargers and twin four-choke carburetors and boasted more than 500 horsepower in methanol-fueled race tune. It also received a dual-magneto ignition system, and each cylinder used two spark plugs.

Castoldi called the boat Arno XI, and on October 15, 1953, he set the water speed record for the 800-kg class by averaging 150.19 mph during a two-way run. Some years passed, and racer Nando Dell'Orto later took ownership. He reportedly made some aerodynamic tweaks, including the shark nose intake and the rear shark fin before eventually retiring the boat from serious racing.

In 2012, the Arno XI emerged from the shadows as lot No. 371 at an RM Sotheby's auction, where it sold for €868,000, or roughly $966,000. Today, it is up for sale in possibly its best condition with the original engine and remains a monumental piece of Ferrari history. See more at DuPont Registry and RM Sotheby's.