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).
Page detailing modifications to camshaft and spring force specifications.
| Identifier | ExFiles\Box 85\3\ scan0049 | |
| Date | 12th January 1938 guessed | |
| -2- (5) A modified ratio of acceleration at changeover to ace at full lift to suit the lower stress springs to LeC. 5417. The excess spring force over that theoretically required at 4500 r.p.m. is 27.4 lbs. at changeover and 24.2 at full lift. The corresponding excess spring force with the standard camshaft and spring is 16 lbs. at changeover and 12 lbs. at full lift. If the bouncing speed of the valve gear with the new camshaft and spring is in excess of 4500 r.p.m. the seat load which is already 5 lbs. less than at present may be further reduced. This camshaft should be available at the same time as the large port cylinder head. E/PSN. | ||