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).
Extract regarding the specification for valves and valve springs on the 40/50 HP chassis.
| Identifier | ExFiles\Box 35\3\ scan 003 | |
| Date | 26th November 1918 | |
| X.276A. Extract from RA/G261118. 1000 - 40/50 H.P. CHASSIS. (10) VALVES AND VALVE SPRINGS. X.29838 X.2563 The valves are to be of the light type, and the valve springs giving ample pressure to permit the engine running up to at least 2500 before leaving the cams, as we have found that many valve springs have been broken through the valve motion jumping the cams. | ||