One of the rarest Porsche ever built is now heading to an auction on May 13th at the Wing, on Silverstone Circuit. St is a factory right-hand drive 1989 Porsche 911 Speedster, one of just 139 ever produced.

The 911 Speedster was first produced in 1989 by Porsche to reflect the design of their original 356 Speedster from the late 1950s. Design cues included the raked aluminium windscreen, three inches lower than the standard car, combined with the ‘double hump’ clamshell fibreglass tonneau cover.

The model was based upon the 3.2 Carrera with its later G50 gearbox, 911 Turbo wide body and chassis and upgraded Turbo-spec brakes and suspension.

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This particular example was delivered in July 1989 by Porsche Cars Australia to Victor Berk of New South Wales, who is its one and only private registered keeper from new. 

It was factory fitted from new with the ‘Super Sport’ equipment option, alarm system, with the luggage compartment trimmed in black velour.

What is more fantastic? The comprehensive history file includes everything from the original dealer order form, a Porsche Certificate of Authenticity (GB), an introduction letter from Porsche Australia to Mr. Berk, every "inspection report" (Australian MOT) carried out by the supplying dealer in New South Wales from new until June 2014, the original Porsche leather wallet and book pack with spare keys, and even the demo cassette for the Blaupunkt audio system.

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Today it has covered a warranted 8,998 kms, which is just 5,590 miles from new. The service book shows 21 main dealer services from new carried out on time, irrespective of mileage covered. The paintwork and interior condition remain exceptional and flawless throughout.

It is now offered for public auction for the first time in its life, estimated at between £145,000 and £165,000.