Ignition timing specifications for the Goshawk engine.
| Identifier | ExFiles\Box 37\1\ scan 248 | |
| Date | 23th October 1923 | |
| X.3949 EFC {E. Fowler Clarke - Electrical Engineer} /T23.10.23. X.3485 - RE GOSHAWK(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) IGNITION TIMING. X.3949. The hand advance allows for 20° advance on the distributor, or 40° on the engine. The automatic advance is 15° on the distributor 30° on the engine. It is understood that the instruction for the setting of the ignition at full retard is 10° a.d.p., in which case the ignition will occur as follows :- Both ranges retarded 10° a.d.p. Hand range retarded with automatic range fully advanced 20° b.d.p. Hand range advanced with automatic range fully retarded 30° b.d.p. Both ranges advanced 60° b.d.p. The Watford R.O.1 magneto range is set at d.p. on retard and 36° b.d.p. on advance. EFC. {E. Fowler Clarke - Electrical Engineer} | ||
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).