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).
Diagram showing battery and magneto ignition timing advance curves.
| Identifier | ExFiles\Box 37\1\ scan 290 | |
| Date | 30th May 1924 | |
| 70° 60° 50° BATTERY IGNITION ADVANCE. (FULLY ADVANCED AUTOMATICALLY) 40° 30° B.D.P. BATTERY IGNITION ADVANCE 30° (FULLY RETARDED AUTOMATICALLY) 20° MAGNETO ADVANCE 10° RETARD. 0° IGNITION LEVER TRAVEL 10° A.D.P. E.A.C. III BATTERY AND MAGNETO 20° IGNITION DIAGRAM. 70° 60° 50° 40° 30° 20° 10° 0° ADVANCE. 10° 20° H.E.W. 29-5-24 E.{Mr Elliott - Chief Engineer} & C. 30-5-24 | ||