How do you improve on one of the greatest of all Ferraris? This 1971 Ferrari 365 GTB/4 Daytona NART Spider provides one answer. There's just five in the world - and this one is set to be auctioned with RM Sotheby's.

The basis of the NART Spider is the Ferrari known universally as the Daytona. US importer Luigi Chinetti commissioned the Italian coach builder Michelotti to create it. NART stands for North American Racing Team and the first NART Spiders were destined for the track.

This example is to road going specification, re-built for Chinetti's wife in 1976 in dark blue over grey with a striking orange-hued leather interior. Her name, Marion, is still visible in white on the doors. A colour keyed hard top was designed for the car at the same time.

The NART Spider has been a multiple concours d'elegance winner. It's unlikely anyone has extended the fully detailed 352 bhp Ferrari V12 to its full extent. Expect a top speed of 170 mph, if you dare.

Opumo

RM Sotheby’s have the Ferrari up for auction, with no estimate yet listed. We’d suggest you’ll have little change from £450,000. Unique.

For full auction information, head to the RM Sotheby’s website.

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