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).
Comparing the specifications of a Claudel carburetter with the performance of an S.U. carburetter on a different engine.
| Identifier | ExFiles\Box 13\3\ 03-page353 | |
| Date | 10th October 1931 | |
| To E.{Mr Elliott - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} X7080. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/AD10.10.31. With reference to your query as to the size of the Claudel carburetter which we use on the P.2. to obtain maximum B.H.P. We find that this carburetter is 2" throttle diameter and 1.8" choke diameter, and the diameter of the diffuser is .63". We have cut the body of the carburetter away round the air entry to allow of freer ingress. The other point we mentioned to you on the phone was that the S.U. carburetter which had 1¾" throttle dia. when fitted to a Japan engine with 112º camshaft and high lift rockers, gave 2.5" depression at 3500 R.P.M. for 84 BHP. so that apparently this size of carburetter is approximately correct for a 3½ litre engine. The power output is not as good as we anticipated from this depression and we are investigating the reason for it. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||