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).
Ignition governor characteristics and timing curves for various engines.
| Identifier | ExFiles\Box 123\5\ scan0315 | |
| Date | 22th February 1939 | |
| 10HH also Hlic. To Rm{William Robotham - Chief Engineer}/RC.{R. Childs} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} c. By/RD. IGNITION GOVERNORS. Until any further modification is requested will you please see that the ignition governor characteristics comply with the following curves for the various engines given below. R.P.M. | Continental Bentley Alum 6 cyl. 8.0 : 1 Comp. Ratio. | B.80 8 cyl. Cast Iron. | B.60 6 cyl. Cast Iron. ---|---|---|--- Start | 250 R.P.M. | 300-350 R.P.M. | 300-350 R.P.M. 500 | 2° + 2° limit | 3° + 2° limit | 5° + 2° limit. 1000 | 6° " | 11° " | 14° " 1500 | 10° " | 18° " | 20° " 2000 | 15° " | 22° " | 23° " 2500 | 19° " | 26° " | 26° " 3000 | 22° " | 29° " | 30° " 3500 | 25° " | 31° " | 32° " 4000 | 27° " | 31° " | 32° " The above figures represent flywheel advance and engine R.P.M. with an initial setting at TDC, this being our standard practice for best idling. The actual units to be checked over for correct governors are (1) Continental Bentley V.{VIENNA} B.V. No.1 Unit. (2) B.80 - Nos. 1 and 2 units and future units. (3) B.60 - Nos.1, 2, 3 and 4 units and future units. | ||