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).
Suspension spring characteristics for the Phantom III and testing procedures.
| Identifier | ExFiles\Box 95\2\ scan0083 | |
| Date | 7th May 1936 | |
| -2- E/Ev.{Ivan Evernden - coachwork}2/MN.7.5.36. In the case of the springs with 10" static deflection the frequency at static load is 59 which is higher than that obtained with the original 10" static deflection springs for 1200 lbs.load, fitted to the Phantom III front suspension, as may be seen from the graph. In fact the graph of the original 10" deflection springs illustrates the cause for the early Phantom III cars being low at the front. We regret that up to the present we have seen no easy means of giving you a scheme for testing constant periodicity on the rear springs, but we shall do so in a short while. In the meantime, we would like to test the constant periodicity of the front suspension coupled with rear springs of the same static deflection. This is a matter which is of great importance in that Wraith II is dependent upon the results. As a precaution we point out that these springs on N.Sch.4807 should be used with the present standard triangles and yoke pieces, and not with the Wraith II type parts which we sent to you a short while ago. EV.{Ivan Evernden - coachwork} Att: N.Sch.4807. | ||