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).
40/50 silencers, detailing power loss, weight, and silence level.
| Identifier | ExFiles\Box 14\6\ Scan189 | |
| Date | 2nd February 1931 | |
| X7230. Rg.{Mr Rowledge} from Rm.{William Robotham - Chief Engineer} Hs.{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3/ME.2.2.31. 40/50 SILENCERS. Herewith curves shewing the power loss in a typical R.R. car exhaust system. The weight of the main expansion chamber and fish tail is 60 lbs approximately. The degree of silence is fairly complete. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Att. | ||