Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Valve lift diagrams, formulas, and clearances for car and aero engines.

Identifier  ExFiles\Box 22\1\  Scan302
Date  17th January 1928
  
E.{Mr Elliott - Chief Engineer} RG.{Mr Rowledge}
BY.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce}
c. to BJ. Wor.{Arthur Wormald - General Works Manager}

X4214

R8/M17.1.28.

X.4214 X.3616
X.4336 X.8060

VALVE LIFT DIAGRAMS FORMULA.

The results from the latest Condor valve lift suggest that we should not depart from our standard practice and quantities, but that we ought to try adding a quick extra clearance part - Hispano, Stutz etc. - to the present foot of about .010" to .020" for aero engine practice, but I fear it would not do for our car practice because of noise, but it could be tried in the smaller amount: therefore add :-

extra clearance *toe rapid
of .010" for car
and .020" for aero,

When next we are designing valve lift cams.


[DIAGRAM]
Graph showing a valve lift curve with labels.
Left label: SAFETY CLEARANCE
Label on the initial part of the curve: SILENT PERIOD
Right label: WORKING CLEARANCE
Top right of diagram: R.{Sir Henry Royce}
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙