Rolls-Royce Archives
         « Prev  Box Series  Next »        

Performance comparison graph between a 108° masked camshaft and a 114° unmasked camshaft.


Identifier  Morton\M19\  img271
Date  29th October 1931 guessed
  
RM {William Robotham - Chief Engineer} P.30.
COMPARISON OF 108° MASKED CAMSHAFT AND
114° E82448 UNMASKED CAMSHAFT
OPEN EX. C/R.47 HIGH LIFT ROCKERS TWIN CARBS 1.4 CHOKES
MASKED CAMSHAFT INLET LIFT .547 EXHAUST .469

Axes:
B.H.P. (vertical left, 80-160)
R.P.M. (horizontal bottom, 500-3500)
INDUCTION DEPN INS HG (vertical right, 2-4)
B.M.E.P. (vertical right, 60-110)

Graph Keys: A, B, C

Diagram C (Top Left):
114° SHAFT E82448
VALVE LIFT INCR. TO .525
C
EX, IN
.020 CLCE
Timings: 22 7.5, 52, 49

Diagram A (Bottom Left):
HIGH LIFT ROCKERS
.020 CLCE
A
EX, IN
Timings: 20 4 18.6, 67.8, 43.8, 41

Diagram B (Bottom Right):
HIGH LIFT ROCKERS
.020 CLCE
B
EX, IN
Timings: 1.5 12, 25.5, 62.5, 38.5, 46.0
  
  
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 🗙