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Performance graph comparing engine configurations with different valve lift timings and a machined head.


Identifier  Morton\M19\  img238
Date  9th August 1931
  
COMPARISON OF VALVE LIFT 114° SHAFT
R.M. P.19
LARGE VALVE HEAD 4.78 C/R 2.0" VALVE THROAT
114° CAMSHAFT ROCKER RATIO STANDARD
TIMING ON C.L.C.E. TWIN CARBS
I.O. 13° B.T.C. E.O. 56.5° B.B.C.
I.C. 58.5° P.B.C E.C. 12° P.T.C.
HIGH LIFT TIMING ON C.L.C.E.
I.O. 24-25° B.T.C. E.O. 54° B.B.C.
I.C. 62° P.B.C. E.C. 18° P.T.C.
VALVE LIFT .525
VALVE LIFT .470
CLAUDEL HIGH & LOW LIFT
HEAD MACHINED TO GIVE A MINIMUM OF .2" CLEARANCE ROUND THE INLET VALVE HEAD.
R.P.M.
INDUCTION PIPE B.M.E.P. LBS/SQ"
SIMILAR CURVES TAKEN WITH CLAUDEL CARB. SHEWED NO INCREASE IN TOP M.E.P. BUT A SLIGHT DROP IN LOW SPEED M.E.P. / 2 Lbs/SQ".
INDUCTION DEPN. ROSE 35 lbs WITH High Lift Rocker.
  
  
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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