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Graph plotting power and detonation characteristics for a Bentley III engine with varying compression ratios.


Identifier  ExFiles\Box 97\1\  scan0131
Date  1st March 1938
  
BENTLEY III.
COMPRESSION RATIO.
POWER & DETONATION.

S.28.
MARCH 1938.

① STD: WRAITH CYL: HEAD (131 cc's)
GASKET .010: C/R = 6.25:1.

② WRAITH HEAD (119 cc's)(.100 OFF FACE.)
GASKET .050 = C/R = 6.3:1.

ⓐ MIN. ADV. FOR MAX. POWER.

ⓑ LINE TO AVOID DETONATION.

VALVE TIMING (@ .030 CL'CE)
I.O. 2° B.T. E.O. 41° B.B.
I.C. 40° A.B. E.C. 3° B.T.

REDLINE PETROL (No 3. SPIRIT.)
PROD. BENTLEY EXH. SYSTEM.
B.III. AIR BEND & SILENCER.

SPEC. HPS {Horace Percy Smith - Experimental Factory Mgr} /C.P.1/VS {J. Vickers} 24-1-38
B.III No. 1 UNIT.

AXIS LABELS:
SPARK POSITION B.T.D.C.
B.M.E.P.
R.P.M.

GRAPH ANNOTATIONS:
C.T.S.
①a
②a
①b
②b
  
  
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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