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).
Higher compression cylinder head, top speed issues, and carburetter settings for chassis GAE-2.
| Identifier | ExFiles\Box 27a\1\ Scan173 | |
| Date | 3rd December 1934 | |
| W/P - Sr. x4013 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}19/KW. 3.12.34. Chassis GAE-2. Poberejsky. With reference to your note to Hs{Lord Ernest Hives - Chair}, Srl/Crn.1.12.34, re the higher compression 20/25 cylinder head. We are to-morrow despatching this to you, together with the necessary cylinder head gasket, and shall be glad to hear your opinion on it in due course. There is one point we should like you to clear up. We cannot understand the top speed of the old 20/25 being the same as the new 20/25, and are wondering whether it is possible that there may be something wrong with the exhaust system of the car with the new carburetter. If they get the clearances wrong it is very easy to put up a lot of back pressure. If the exhaust systems are interchangeable it would be rather interesting to make the test. Another point which might be of interest to you would be to fit an oversize jet just to make sure that the carburetter is not too weak at top speed. It is not much good strengthening up the mixture control because the needle is almost parallel at the top. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||