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).
Use of specific valve springs and their effect on performance and timing gear rattle.
| Identifier | ExFiles\Box 106\5\ scan0065 | |
| Date | 19th July 1932 | |
| Y5060 ? Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} from E.{Mr Elliott - Chief Engineer} c. By.{R.W. Bailey - Chief Engineer} Mx.{John H Maddocks - Chief Proving Officer} E.7/HP.19.7.32. Valve Springs 20/25. Referring to your memo Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3/AD.15.7.32, we should like to know if the reduction in bouncing speed of 100 r.p.m. is due to surging or merely to decrease of spring pressure at the end of the deceleration period. If the latter then there appears to be no serious reason why the springs to HS.{Lord Ernest Hives - Chair}477 (E.58525) should not be used as their defect will only be noticeable on third gear in reducing the maximum performance on this ratio from 60 to 58.5 m.p.h. whereas the smoother camshaft torque obtained by their use may be of considerable value later on in avoiding timing gear rattle when the engine becomes freer and the gears more slack. E.{Mr Elliott - Chief Engineer} RECEIVED 1932 JUL 20 | ||