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).
Test report on valve spring performance and measurements during endurance runs.
| Identifier | ExFiles\Box 106\5\ scan0063 | |
| Date | 12th July 1932 | |
| X 5060. Copy for Files. 12.7.32. VALVE SPRINGS. 20/25. Springs E.58525 (Hs.{Lord Ernest Hives - Chair}477) Camshaft E.57177 (112º) Cotters. E.70315 (Cams to E.57175) Under the above conditions, endurance runs were carried out. at 3500 R.P.M. for 15 minutes. at 3750 R.P.M. for 10 minutes. Valves bounce at 3800 R.P.M. With E.58524 cotters fitted, valves bounce at 3600 R.P.M. Length of spring. (Valve closed.)- Inlet { With standard cotters E.70315 1.560 { " cotters E.58524 1.640 Exhaust { With standard cotters E.70315 1.660 { " cotters E.58524 1.740 When first assembled with new felt packing, there is clearance of .080 (approx) between lower washer and cylinder head. In time when felt packing settles down, the washers in most cases lie flush on the cylinder head. Hs{Lord Ernest Hives - Chair}/C.T. Salt. | ||