According to Excellence was expected in the Autumn of 1966, with the introduction of the 1967 Model year 911S Porsche offered several 'upgrade kits' in a special catalogue (Catalogue# W171)

This catalogue included a 'blueprint' of a competition exhaust.

Sport Kit II, however, included a special rally system which is described by the following statement: 'Sportauspuff uses two big bore outlets to give freer vent to the exhaust and helps to increase performance by 15hp.

Has anyone ever seen this catalogue as I really need to find a copy to help with some eligibility issues for a Historic Race Championship.

Thanks