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).
Modifications to the Aluminium Bentley Cylinder Head, specifically the use of steel washers and new collars for double valve springs.
| Identifier | ExFiles\Box 86\1\ scan0069 | |
| Date | 21th June 1934 | |
| X219 Rm{William Robotham - Chief Engineer} To ~~BY~~. from E/JNR.{Charles L. Jenner} E/JNR.{Charles L. Jenner}6/HP.21.6.34. c. ~~Hs{Lord Ernest Hives - Chair}~~ RHC.{R. H. Coverley - Production Engineer} re Aluminium Bentley Cylinder Head. Ref.RHC.{R. H. Coverley - Production Engineer}4/BE.12.6.34. We agree that when double valve springs are fitted to the aluminium head, it is necessary to have a steel washer between the valve spring and the casting. Since we are not able to machine any more away from the head the only way to do it if we use the same valve springs is to make new collars at the top of the valve. This we have done on LeC.3993. At the same time we have introduced the valve retaining spring rings. E/JNR.{Charles L. Jenner} 2 1/2 - 1 | ||