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).
Single-cylinder unit modifications and valve mechanism deflection.
| Identifier | ExFiles\Box 17\6\ Scan295 | |
| Date | 27th July 1934 | |
| -3- (4) Cont'd.{John DeLooze - Company Secretary} We understand that you are already contemplating a single cylinder unit of the high power head type having two inlet valves, and in view of the fact that the alternative is a 1.7 diameter single valve we are very much in favour of the proposed modification. (5) Deflection in Valve Mechanism. So far we have been unable to substantiate that the appreciable amount of deflection which undoubtedly does take place in our valve gear, has any very definite influence with regard to lowering the speeds at which the valves bounce. We have also little evidence to shew that high positive accelerations on the camshaft cause excessive valve spring surge, actually the 20/25 valve springs have worse surge periods than those on the Bentley. Ha/Rm.{William Robotham - Chief Engineer} | ||