Daily report on petrol consumption tests for a Paulin Bentley II at Montlhéry.
| Identifier | ExFiles\Box 160\3\ scan0096 | |
| Date | 24th January 1939 | |
| To. Rm. {William Robotham - Chief Engineer} from Rm {William Robotham - Chief Engineer} /GR. {George Ratcliffe} 1379 Levallois. Rm {William Robotham - Chief Engineer} /GR. {George Ratcliffe} 1/JAB.24.1.39. DAILY REPORT Paulin Bentley II.- B-27-LE. Petrol Consumption Tests at Montlhéry. 1.7/8" S.U.carburetters complete with dampers and air silencer. IndiaProduction 20 HP. with 4-speed box and Front Wheel Brakes Tyres 6.50 x 17" at 30 lbs/sq" cold. LM.8 needles fitted and control in normal position. With correct idling mixture the part throttle economy is correct and if weakened further misfires occur. Best performance setting gave the following figures all taken on the overdrive gear. The mileage recorded was the most accurate on the 6.50 x 17" IndiaProduction 20 HP. with 4-speed box and Front Wheel Brakes Tyres at 30 lbs/sq". R.P.M. M.P.H. IGN. M.P.G. 1250 40 T.D.C. 30.5 " " 12° B.T.D.C. 32.5 1950 60 T.D.C. 24.0 " " 12° B.T.D.C. 26.0 Water temperature then failed to 60°c. Thermostat cover dismantled bellows not disturbed. Nothing found wrong, so re-assembled. Believe failure due to valve sticking open (no evidence). Water temperature O.K. again at 83°c. R.P.M. M.P.H. IGN. M.P.G. 2500 80 T.D.C. 20.5 " " 12° B.T.D.C. 21.0 2800 90 T.D.C. 16.5 " " 12° B.T.D.C. 17.0 3100 100 T.D.C. 13.0 Track surface " " 12° B.T.D.C. 14.0 made readings inaccurate at 100 m.p.h. The small increase in m.p.g. by advancing the ignition on such good consumptions does not warrant the driver messing about with the control, detonation being very bad if forgotten and left in the advanced position when accelerating at full throttle. | ||
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).