Valvegear answers

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Bob Chamberlain’s request for information about the 1912 Prince Henry Austro-Daimlers has been answered, Porsche of Germany coming up with the required information.

The engine had been quoted as having one inlet valve and four exhaust valves per cylinder, but this is erroneous — there were two valves per cylinder, all in detachable cages (which was unusual), the exhaust cages or ports being cooled by fins. Operation was by rockers working below the valve-springs, spring-tension being maintained by little columns passing through the spoon-shaped rocker-ends.

HR Godfrey, along with Chamberlain’s uncle, the famous pilot Harry Hawker, had one of the 70 replicas of these 27/80hp Austro-Daimlers which were sold to the public (these had carden-shaft drive, whereas the competition cars had chain-final-drive), and copied this valve-gear for the racing GN “Kim”. It may have been unusual but it worked, and Austro-Daimlers finished 1-2-3 in the 1912 Trials. WB