Classic Ferraris fetching huge sums at auctions is not an unfamiliar theme, but this 1964 275 GTB that’s set to go under the hammer in a fortnight at Gooding and Company’s auction in Scottsdale, Arizona, is a bit unusual.

For starters, this delectable yellow coupe is the one-and-only prototype that preceded the production-spec 275 model line. It served as a test bed for tech that was new (at the time) for the prancing horse, and this included independent rear suspension and a transaxle layout (ie gearbox mounted in unison with the rear axle). The prototype also featured the new 3.3-litre V12 that would be used in the 275.

These credentials alone make this a prized Ferrari, but it scores added kudos as it’s also backed by a unique racing history. While Ferraris competing on circuits around the world is nothing unusual, this prototype was an entrant in the 1966 Monte Carlo Rally, which at the time was even more of an iconic event than it is today.

Although the prototype – which features Scaglietti longnose bodywork – had already completed 12,000km of on-road testing, it was modified for the Monte Carlo Rally via auxiliary lights, reinforced glass, a limited-slip differential, a radiator cover, custom bonnet and an additional windshield wiper.

The car was unable to finish due to drivetrain issues, but its driver, Giorgio Pianta, described the experience as “the most beautiful memory of my life”.

Over the years since then, the car has circulated through the hands of several owners and was even painted red at one point. However, it’s now back in its factory yellow paintwork and it also features its original engine.

Gooding and Company says the Ferrari will need to be given a thorough mechanical inspection and overhaul before it's driven, but that shouldn't be a big issue for any bidder that manages to stump up the $6-8m (Dh22-30m) it will take to win the car.