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).
Tests conducted on an air intake silencer for a 25 HP car, including sketches of the modifications.
| Identifier | ExFiles\Box 25\1\ Scan037 | |
| Date | 2nd January 1933 | |
| 84688, E.{Mr Elliott - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/G.H. Wayman. c. By.{R.W. Bailey - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} Hs{Lord Ernest Hives - Chair}/GHW.7/KT.2.1.33. x5080. AIR INTAKE SILENCER FOR 25 HP. CAR. Our first tests were carried out on 18.G.IV. car to which we fitted the latest type Tank engine carburetter. This carburetter was fitted with an air cleaner, and had a common air intake feed to both main air port and air valve port, as per sketch :- GAUZE Sketch 1. CARB The carb. roar was very much worse than the standard 25 HP. carb. and so we removed the air cleaner entirely. This improved the roar quite 25%. We then fitted a plain tube between the top and bottom air cleaner castings, and drilled a hole in the top casting 2.0" in diameter, thus sending the air in one downward direction (see Sketch 2) instead of (as in Sketch 1.) two directions, one upwards and one downwards. CARB Sketch 2. CARB | ||