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 roughness and exhaust vibrations in the 20 HP chassis.
| Identifier | ExFiles\Box 57\1\ Scan137 | |
| Date | 21th May 1925 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Y5770 Expl. No. REF: Hs{Lord Ernest Hives - Chair}6/LG21.5.25. To CWB. from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to PN.{Mr Northey} 20 HP. CHASSIS. Y5770 X42G We believe R.{Sir Henry Royce} had in mind major alterations when he said there was not likely to be any alteration in the design of the car, he realised that there will always be improvements to be made. With reference to the two features you mention - (1) Engine roughness between 18 and 30 m.p.h We have been on a great number of 20 HP. cars on which this fault is not manifest. The 20 HP. car which Mr. Royce has used for a considerable time does not suffer from his complaint. The fact some cars are free from it proves that it is not entirely a question of design. Experiments are being carried out with different crankshafts but it is unlikely that there will be any alteration on production chassis for some time, also, we cannot say that this alteration would make any improvement to the complaint you describe. (2) Vibrations set up in exhaust system. We have received a design from WW. which should reduce this. It will be fitted to all F.W.B. cars. Hs.{Lord Ernest Hives - Chair} | ||