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 valve springs and washers for the Phantom II and 20/25 HP chassis.
| Identifier | ExFiles\Box 56\2\ Scan104 | |
| Date | 29th September 1930 | |
| c.Hs.{Lord Ernest Hives - Chair} X290 BY/EM5/J.29.9.30. RECEIVED SEP 29 1930 H Valve Springs. With respect to Mxl/T.19.9.30, with regard to the above, will you kindly note the action which has been taken to reduce the clearance between the valve springs and washers is as follows:- a/- Phantom II Chassis. Commencing at 'N' Series the diameter of the springs will be reduced to 1.110" plus 10 and the length of the bottom spigot will be increased by 50%. The springs will also be made semi open ended. b/- 20/25 H.P Chassis. In this case both washers and springs for the whole series have been produced and we are therefore proposing to withdraw the bottom washers and produce a further quantity where the spigot on the bottom washer has been increased to .105" and the diameter of the spigot increased to 1.100" minus five. BY/EM. | ||