He was dismayed to discover that there was another 330 P with the same chassis number in the Maranello Rosso museum at Ferrari’s headquarters near Modena, northern Italy.

This week a five-year legal battle came to a head when a court in Modena appointed an independent expert to answer a question that has gripped the world of racing enthusiasts: which Ferrari is the clone?

According to the carmaker, three 330 P models were made, each with a 12-valve, 4-litre, 360bhp engine. The fate of two is known: one (chassis No 0820) is in the US, and the second (0822) in France.

But what happened to the car (chassis No 0818) in which Hill and Joachim Bonnier came second in the 1964 24-hour Le Mans race and which Ludovico Scarfiotti and John Surtees drove to victory at the Nürburgring track in Germany the following year?

Sandra Lodi, who runs the Maranello Rosso collection, said that Ferrari had the authentic vehicle, which was wheeled out three years ago to star in an Italian television biography of Enzo Ferrari, the company’s founder.

Carolina Gentili, the Modena judge hearing the case, said that she had asked Adolfo Orsi, a racing-car expert, to decide which of the Ferraris was genuine. Mr Orsi checked and tested this week the one at Maranello, which has been given a “certificate of authenticity” by the company’s experts.

That, Ms Lodi said, “should be enough to satisfy anyone”. Mr Hofer, however, said that issuing the certificate had been “a huge error” that had shocked racing-car enthusiasts. “My car, which I bought in 1967, has all the original documentation,” he said.

Mr Hofer said that he had refused to take the car to Italy to have it checked at Maranello. “They have already decided that theirs is the authentic one. The moment I drive mine in, they will brand it a fake.”

He said that he had invited Mr Orsi to travel to Salzburg, at his own expense. “Alternatively I will drive the car to the border between Austria and Italy and they can carry out their examination there.”

One theory is that both Ferrari and Mr Hofer may be right: racing cars damaged on the track are often sold off to enthusiasts who rebuild them, and sometimes use different components to construct more than one version.

According to some experts, the disputed 330 P was broken up after it was crashed fatally by the racing driver Dick Protheroe at Oulton Park in 1966 and the wreck was sold by his widow. Some parts were incorporated into Mr Hofer’s car, others into a second car that was restored in Britain and later turned up in the US, where it was confiscated by the FBI from a drug trafficker and, eventually, sold back to Italy.

Gianni Rogliatti, author of Ferrari: Design of a Legend, said that this did not solve the mystery, as both cars could not have the same original chassis number. “The truth will emerge — but it takes time,” he said.

• 4,622.64 Kilometres Graham Hill and Joachim Bonnier covered in 24 hours at Le Mans in 1964

  Source: Le Mans Register

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