Ferrari has a history of breaking auction price records, but a 1957 Testa Rossa racing prototype has been tipped to push the bar even higher.

The car comes up for sale in August at the Pebble Beach Concours d'Elegance sale, and experts are predicting it will smash the previous $12 million (£7.4 million) paid for another 250 TR in 2009.

Chassis number 0666 was the prototype for all 22 of 250 TRs ever made. It has a 3.0-litre V12 engine, is right-hand drive and was campaigned in the Nürburgring 1,000km race before competing in the Grand Prix of Sweden.

It was later modified with pontoon-fender bodywork by Scaglietti and raced in South America. Later, it took part in races in America and at Le Mans.

David Gooding, of auction firm Gooding and Company, said: "We will witness a historic day when this incredible car, which is one of the greatest race cars of all time, crosses the stage in Pebble Beach."