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).
20 HP manifold and silencer system, questioning the source of increased noise.
| Identifier | ExFiles\Box 6\7\ 07-page046 | |
| Date | 1st April 1929 | |
| X.5230 Rm.{William Robotham - Chief Engineer} from DA.{Bernard Day - Chassis Design} DA{Bernard Day - Chassis Design}1/MS. 4. 29. With reference to Hs{Lord Ernest Hives - Chair}/RaS/LG27.3.29., the standard 20 HP. manifold is cast. Further the pipe at the moment goes into the centre of the silencer. Do you mean that you want a front expansion box like the SS.{S. Smith} with an intermediate expansion box in the front end of the silencer? If this is so we would get out a scheme for you, but the silencing system on the 20 HP. is exactly the same as the old one, and it is difficult to see why there should be a difference in the noise. Do you attribute it to the turbulent head and larger valves? DA.{Bernard Day - Chassis Design} | ||