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 charting the results of Bentley single-cylinder engine tests on the effect of improving the valve orifice coefficient.
| Identifier | ExFiles\Box 133\2\ scan0121 | |
| Date | 1st November 1934 guessed | |
| BENTLEY SINGLE CYLINDER TESTS. SHEET 2 EFFECT OF IMPROVEMENT OF VALVE ORIFICE COEFFICIENT. (SEE ALSO SHEET 3) "CLOSE-CENTRES" HEAD (L.C. 4100) AEROLITE PISTON ZENITH TRIPLE DIFFUSER CARBURETTOR (32% CHOKE) OPEN EXHAUST FUEL : DTD 224 NORMAL BENTLEY TIMING NOTE: TO PREVENT CRAMPING THE B.H.P. CURVES, NOS 1 & 4, ARE NOT CONTINUED DOWN TO THE LOWER ENGINE SPEEDS. CURVE 1 = INLET VALVE 1.4" DIA; EXHAUST 1.25" DIA; C.R. = 6.5 CURVE 2 = INLET VALVE 1.4" DIA; EXHAUST 1.3" DIA; C.R. = 6.5 CURVE 3 = INLET VALVE 1.5" DIA; EXHAUST 1.3" DIA; C.R. = 6.35 CURVE 4 = INLET VALVE 1.5" DIA; EXHAUST 1.4" DIA; C.R. = 6.35 CURVE 5 = AS 4, BUT WITH INLET PORT ENLARGED TO 1.5" DIA, & VALVE GUIDE BOSS REMOVED. BRAKE HORSE POWER R.P.M. B.M.E.P. (LBS/SQ.IN) | ||