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).
Secret internal memorandum discussing the development of an automatic ignition advance system and other modifications for the 40/50 model.
| Identifier | ExFiles\Box 37\1\ scan 292 | |
| Date | 1st September 1924 | |
| X3949 TO HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} SECRET. R4/M5. 9.24. Copy to C.I. " " EBG. E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C.11. IGNITION &C. COMBINED AUTOMATIC ADVANCE BY RELAY. Y3949 X8680 We have nearly completed the R-R automatic combined advance for the magneto and battery ignitions. Investigations for this point out that the "Scintilla" magneto is hardly suitable for our purpose. The total advance of the automatic advance seems insufficient for the requirements of the engine because we understand it is less than the sleeve Watford which is 55o on the magneto and therefore 37o on the engine crankshaft. We do not ask for any serious changes on the engine except a small increase in the diameter of the flange carrying the ignition tower. If we could have a crankcase with this requirement pushed through with all possible speed, it would help to save time as the whole scheme seems very hopeful and passably simple. In addition to this work we are sending you this week the modified cross member to permit of the 23" matrix radiator, and a rough drawing shewing the general arrangement of the modification to the exhaust system. We hope you will be able to rig this up out of sheet metal work so that the scheme can be tested quickly. This scheme should have the cutout on the rear end of the main silencer as sent through some time ago. We hope also to send the modification to the steering column so as to fit the present 40/50 controls very much as they are intended for the latest 40/50s - i.e. klaxon, single wire earthing press button in the centre, the carburetter control, governor, and ignition control. The ignition control is to have in the instruction book a technical diagram shewing the setting of the magneto and battery ignitions for the various positions of the control lever. The more important positions should be checked on every car. The requirements may be slightly modified when we fit the new head to the engine, but we think this will not be ready for the first batch of speed model cars, and we expect it will be easier to obtain than the engine under consideration. R.{Sir Henry Royce} | ||