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).
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.{Sir Henry Royce} DUPLEX. CARB. 222 CU. INS. CURVE (∆---∆): 20/25 5.8 C/R.{Sir Henry Royce} 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.{Sir Henry Royce} CURVE (*---*): CADILLAC 452 CU. IN. V-16 DUPLEX DOWNDRAFT CARBURETTERS - 6.49 C/R.{Sir Henry Royce} | ||