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Power comparison graph for the 20/25 HP and 25/30 HP engines, plotting BHP and BMEP against RPM.


Identifier  ExFiles\Box 20\9\  Scan096
Date  2nd January 1936
  
20/25 H P AND 25/30 H P
POWER COMPARISON
OPEN EXHAUST

① 20/25 ENGINE (H7S)
COMP RATIO 5.25:1
CARB TYPE 3877
CYL BORE 3.250 DIA
Handwritten: Present, Standard

② 25/30 ENGINE G.6 (TURBULENT E.G.3868)
NON PIPE E.80870
COMP RATIO 6.0:1
STROMBERG DA {Bernard Day - Chassis Design} 42 CARB
CYL BORE 3.500 DIA
Handwritten: Proposed Product, Early Type

NOTE. CAMSHAFT & VALVES ARE THE SAME ON BOTH ENGINES

③ COMP RATIO 6.0:1
(NON-TURBULENT E.G.5806)
NON PIPE H.S. 2014
STROMBERG DA {Bernard Day - Chassis Design} 42 CARB
CYL BORE 3.500 DIA
OTHERWISE AS ①
Handwritten: Test for Cars

AXIS LABELS:
B.H.P.
B.M.E.P.
R.P.M.
  
  
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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