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).
Revised specification for the Goshawk II battery ignition governor spring and advance timing.
| Identifier | ExFiles\Box 54\5\ Scan163 | |
| Date | 28th October 1921 | |
| To Da. {Bernard Day - Chassis Design} from E. {Mr Elliott - Chief Engineer} c. to CJ. c. to Hs. {Lord Ernest Hives - Chair} c. to Wor. {Arthur Wormald - General Works Manager} c. to Ry. X3485 E8/G28.10.21. Z.3485. RE "GOSHAWK II" BATTERY IGNITION. X.3949. In our drawing LeC.1432 of the "Goshawk II" battery ignition, it is specified that the governor should work between engine speeds of 0 and 3000 R.P.M., and give an automatic advance of 40 degrees on the crankshaft. The governor spring was also specified as 10 turns of 16 S.W.G. wire of mean diameter .360" and to be not set up in the initial position. Mr. Royce has now altered the specification of the ignition advance by his memo R17/G27.10.21, and we should be glad if Derby would calculate a new spring which will be set up in the initial position so that the governor will not start to advance until 500 R.P.M., after which it should automatically advance 35 degrees before dead point at 500, and 45° before dead point at 3000. We consider this is the most practical specification to set from the table of experimental results given in Hs {Lord Ernest Hives - Chair} 9/LG27.4.21. E. {Mr Elliott - Chief Engineer} | ||