Graph of engine S.S. Oil Pressures versus RPM for different valve and spring configurations.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan055 | |
| Date | 30th August 1929 | |
| S.S. OIL PRESSURES. ENGINE No S.S.15. STANDARD OIL PUMP. OIL TEMPERATURE = 60°C. ______ STD. RELIEF VALVE. _ _ _ _ WEAK SPRINGS (V694). -- -- -- DURALUMIN BALL VALVES & WEAK SPRINGS (V694). _._._._ DURAL. BALL & WEAK SPRING IN L.P. VALVE ONLY (No BALL IN I.P. VALVE). OIL PRESSURE (LBS / SQ. IN.) R.P.M. OF ENGINE. MAIN PRESSURES. INTERMEDIATE PRESSURES. LOW PRESSURES OMITTED TO AVOID CONFUSION. | ||
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).