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Graph comparing the Brake Mean Effective Pressure curves for various Cadillac, Bentley, and 20/25 R.R engines.


Identifier  ExFiles\Box 93\5\  scan0011
Date  13th February 1935 guessed
  
G.M.C. CORRECTION TO 103°F. {Mr Friese}
BRAKE MEAN EFFECTIVE PRESSURE CURVES
CADILLAC & ROLLS - ROYCE PRODUCTS

Y-AXIS LABELS (LEFT):
B.M.E.P.
LBS/Sq In:
DEGREES
H.P.

Y-AXIS LABELS (RIGHT):
LB/FT
LB/H.P. HR. FUEL X 100 - AIR X 10
PER CENT (10)

X-AXIS LABEL (BOTTOM):
R.P.M. (÷100)

CURVE LABELS ON GRAPH:
SIXTEEN DUPLEX CARB DOWNDRAUGHT 6.49 C/R
BENTLEY
SIXTEEN SINGLE UPDRAUGHT 6.49 C/R
20/25 R.R

TABLE 1 (CENTER):
TITLE: DURATION, TIMINGS .020 TAPPET CLEARANCE
COLUMNS: [MODEL], INLET, EX, Ex. O. {Mr Oldham} , Ex. C., IN. O. {Mr Oldham} , IN. C.
CADILLAC V.12: 204, 206, 25° B., 1° A. {Mr Adams} , 15° A. {Mr Adams} , 39° A. {Mr Adams}
CADILLAC V.16: 197, 196, 23° B., 6° B., 15° A. {Mr Adams} , 31° A. {Mr Adams}
LA {L. A. Archer} SALLE LINE 8.: 210, 210, 30° B., T.D.C., 11 A. {Mr Adams} , 41° A. {Mr Adams}
STANDARD 20/25: 213, 230, 44 B., 6° A. {Mr Adams} , T.D.C., 40.5 A. {Mr Adams}
BENTLEY 3 1/2 LITRE: 234, 238, 47 B., 11° A. {Mr Adams} , 1.B., 52.5 A. {Mr Adams}

TABLE 2 / LEGEND (BOTTOM RIGHT):
COLUMNS: ENGINE MOD & SERIAL N°, TEST DATE, POWER & ECONOMY, OBJ. CORR., B.M.E.P. CURVES
CURVE (x---x): BENTLEY 6.4 C/R. DUPLEX. CARB. 222 CU. INS.
CURVE (∆---∆): 20/25 5.8 C/R. 222 CU. INS LATEST S.U. CARB.
CURVE (♦---♦): LA {L. A. Archer} SALLE 5.9 C.R. 240 CU. INS. 8 CYL. DUPLEX CARB.
CURVE (*): G.M.C. CORRECTION 60°F LA {L. A. Archer} SALLE 5.9 C.R. LIFTED .25 CU. INS.
CURVE (o---o): CADILLAC 368 CU. IN. V-12 STD UPDRAFT CARBURETTERS - 5.59 C.R.
CURVE (o-*-o): CADILLAC 452 CU. IN. V-16 STD UPDRAFT CARBURETTERS - 6.49 C/R.
CURVE (*---*): CADILLAC 452 CU. IN. V-16 DUPLEX DOWNDRAFT CARBURETTERS - 6.49 C/R.
  
  
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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