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).
Engine valve spring pressure and rating in relation to air flow.
| Identifier | ExFiles\Box 43\3\ Scan097 | |
| Date | 21th December 1926 guessed | |
| contd :- -2- With the higher spring rating and sufficient maximum spring pressure, say 60 lbs. there should be very little risk of rollers leaving cams at top, and also very little risk of broken springs. Thanking Mr. Bailey for his remarks, we are all pretty well agreed, though I am more inclined to think it is the air current past the valve discounting the spring pressure simply, rather than surging of the air in the cyl. however it seems we must have more spring margin while closing. R.{Sir Henry Royce} | ||