Rolls-Royce Archives
         « Prev  Box Series  Next »        

Optimum camshaft timing and performance results from engine tests.


Identifier  ExFiles\Box 1\10\  B001_X106 TO X 110-page039
Date  12th July 1932
  
-2- Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} 7/MA.12.7.32.Cont'd. {John DeLooze - Company Secretary}

The optimum camshaft from these tests would appear to be the following timing :-

[Diagram showing camshaft timing with values: EX 34, IN 34, 2, 6]

The best low speed power results would be obtained with the minimum length of toe for silence between .003"& .013"valve lift, and the quickest lift practical between .013"& .020"

With this camshaft, small valves long reach plugs, an effective hot spot and 6/1 C.R. we should get 105 M.E.P. at 1000 R.P.M. which we think will be reasonable and we should top 70 B.H.P at 75 M.P.H. which is a fair compromise. In studying these curves it should be noted that the single S.U. is not ideal with our 6 part pipe for distribution below 2000 R.P.M. and we are fixing up a better system.

Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer}
  
  
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).


Copyright Sustain 2026, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙