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).
'SS' valve springs, proposing the use of standard Phantom springs with modifications.
| Identifier | ExFiles\Box 17\6\ Scan064 | |
| Date | 13th November 1928 | |
| By.{R.W. Bailey - Chief Engineer} from Hs.{Lord Ernest Hives - Chair} c. to wor.{Arthur Wormald - General Works Manager} X7060 Hsl/LG13.11.28. 'SS{S. Smith}' VALVE SPRINGS. X7060/X290 At the moment the SS.{S. Smith} double valve springs are still in the experimental state, there being one or two troubles to overcome before they could be regarded as satisfactory. The SS.{S. Smith} inlet valve weighs 4.46 ozs. and exhaust 5.23 ozs., this latter weight being the same for both inlet and exhaust on the standard Phantom. The SS.{S. Smith} cams also require slightly less deceleration from the springs therefore we appear justified in using standard Phantom springs. We however desire to retain the same clearance between the coils when the valve is closed as on the Phantom. This will mean modification to the top and bottom washers to obtain more spring room. We should therefore like to have a scheme prepared to enable us to use standard Phantom springs as we expect the SS.{S. Smith} engine will go into production with these springs. HS.{Lord Ernest Hives - Chair} | ||