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).
Comparative stiffness, deflection, and rating of 'SS' springs versus the standard 40/50 HP springs.
| Identifier | ExFiles\Box 16\7\ Scan166 | |
| Date | 11th April 1929 | |
| BY.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to DA.{Bernard Day - Chassis Design} X7410 Hs{Lord Ernest Hives - Chair}/Rn{Mr Robinson}7/LG11.4.29. 'SS{S. Smith}' SPRINGS. Hs.{Lord Ernest Hives - Chair} said that R.{Sir Henry Royce} mentioned that he wanted the S.S. springs to be 10% stiffer because the rating was now so low that the back of the car fell or rose too much when the passengers got in and out. We think that R.{Sir Henry Royce} and Hs.{Lord Ernest Hives - Chair} were both under the impression that the S.S. springs were of much lower rating than the 40/50 HP. Actually all 40/50's now are sprung for normal load with a buffer clearance of 4.125" which gives an initial spring deflection of 8". The S.S. is sprung for normal load with a deflection of 8.250" so that the actual difference in the effective rating of the two springs is only 3%. We therefore are holding the instructions for the 10% stiffer S.S. springs over until we hear further on the subject. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||