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).
Valve spring performance and requirements for use with Cadillac silent tappets.
| Identifier | ExFiles\Box 17\6\ Scan232 | |
| Date | 4th June 1934 | |
| x7060 To E.{Mr Elliott - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}5/KW.4.6.34. Valve Springs. With reference to your query as to the valve springs required to enable Cadillac silent tappets to be used on the present standard camshaft. The springs we have been running on the Test Bed and which with the standard valves will be able to run up to about 3,400 revs give a load on the valve seats of 110 lbs. They are badly overstressed and we are having springs made up to the attached specification to replace them. The disadvantage of this arrangement is that with such a high seat load the valve noise is emphasized. With the old standard camshaft we anticipate that we shall be able to use the present valves and valve springs and run up to 3,500 revs., but we are just checking this over again. Naturally both arrangements will benefit from the lighter exhaust valve you are designing. Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}: Att: Memo. Hs{Lord Ernest Hives - Chair}/Smth.24/KW.31.5.34. (In RHC.{R. H. Coverley - Production Engineer} File). | ||