Fake or Fortune

When considering the purchase of a 911 Turbo S or 911 Turbo SE (slantnose), the old adage 'buyer beware' is unfortunately very true. The factory produced a number of variants of the 911 slantnose over time, some cars leaving the factory as a slantnose, others being converted using factory parts retrospectively. In addition, there are a multitude of after-market firms that produced replica parts that makes it even more difficult to sort out flachbau facts from fiction. The disparity in values between genuine cars and 'converted' cars is significant, so it makes sense to take all reasonable steps to validate a car's provenance.

In the past, it has been possible to have your Porsche importer arrange for a Certificate of Authenticity (now Certificate of Production). Porsche did keep record of those cars manufactured in Stuttgart as a Flachbau or Slantnose from factory, and whilst the Porsche Archive is a good resource, cars converted as 'used' vehicles by the factory or from new by accredited US dealers (M505) are less well documented. In such cases information requests will most likely be returned as 'manufactured as a standard 930'. Furthermore, the slantnose was not officially available in the US until the launch of the M505 option in 1987. 

Factory cars made from the 1987 model year (M505 / M506) will have the 505/506 option code displayed on the factory sticker on the reverse of the bonnet/hood and in the log book when the car was supplied. Earlier 'Special Wishes' cars did not have any such option codes displayed.


However, there are a number of key areas in the links below that can be used to help verify the authenticity of factory slantnose models:

Bodywork Authenticity

Interior Authenticity

Mechanical Authenticity


If you have found what seems to be a genuine car, next you also need to consider a buyer's checklist, find out more


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