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).
Specifications for platinum point gap, contact breaker timing, and armature core flux.
| Identifier | ExFiles\Box 48\3\ Scan086 | |
| Date | 6th January 1921 | |
| -7- Contd. (22b) Platinum point gap :- .014" Contact breaker timing :- | | Make. | Break. | |---|---|---| | A. {Mr Adams} | +17° | 91.5° | | R. {Sir Henry Royce} | 64.5° | 139.5° | | | Retarded. | Advanced. | |---|---|---| | Make. | 64° | +17° | | Break. | 139° | 92° | | Make. | 245° | 197° | | Break. | 320° | 271° | Make ratio :- .415. (23) Armature core flux | Speed. | Flux. | |---|---| | 400 | | | 800 | | | 1200 | | | 1600 | | | 2000 | | | 2400 | | | 2800 | | 6.1.21. FC. R.R. 518a (100 T) (S.H. 159, 11-8-20) G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 2500 | ||