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).
Secret memo discussing the failure of Spectre valve springs and requesting a new design and testing rig.
| Identifier | ExFiles\Box 96\2\ scan0026 | |
| Date | 23th February 1935 | |
| SECRET. X352 To E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to By.{R.W. Bailey - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}6/KW. 23.2.35. SpectreCodename for Phantom III Valve Springs. In order to prevent valve bounce with the silent tappets we have been running with valve springs Hs.{Lord Ernest Hives - Chair}1607, which are stressed up to about 94,000 lbs/sq.in. It is not therefore surprising that we have already broken three of these on the road. Additionally, they have a nasty surging period at 4,000 r.p.m., which is audible. This spring is a modification of E.85317. We should be glad if you would look into the design of a suitable spring. As soon as we can get a spare crankcase and some bits we are going to fix up a valve spring testing rig for the SpectreCodename for Phantom III, similar to the one we made for the phantom. This should at the same time enable us to run an endurance on tappets. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||