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Secret memo discussing the slow running performance of the E.A.C. engine and proposing carburetter control modifications.


Identifier  WestWitteringFiles\M\October1924-December1924\  Scan6
Date  1st October 1924
  
ORIGINAL

TO HS. {Lord Ernest Hives - Chair} FROM R. {Sir Henry Royce}

SECRET.

R7/M6. 10. 24.

Copy to C.L. (Struck through)

E. {Mr Elliott - Chief Engineer} A. {Mr Adams} C. 11.

SLOW RUNNING.

X8770 X8240 (Handwritten)
X8771 X8080 (Handwritten)

I was interested to learn that the slow running of the E.A.C. engine on the test bed is equally as good as that obtained with the standard 40/50. engine. I presume this was without any additional friction such as would be obtained by the dynamometer being coupled up to it. Nevertheless, I still feel that with the overhead valve type of engine that we still may have some inherent difficulties in consistently obtaining good slow running.

I should like you to try coupling up the hand control on the steering column to the starting carburetter and main throttle slow running arm, the foot accelerator dealing with the main carburetter only. The starting carburetter control on the instrument board should then be coupled up to the mixture needle of the starting carburetter, so that a rich mixture could be obtained for starting, and a normal mixture for ordinary very slow running when the engine is warm. In this way we should have the engine running on a very tiny carburetter, and I think it would be a very good proof if E.A.C.11. will slow run satisfactorily.

R. {Sir Henry Royce}
  
  
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).


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