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 contact breaker timing and automatic advance characteristics.
| Identifier | ExFiles\Box 40\2\ Scan145 | |
| Date | 11th October 1926 guessed | |
| -2- (4) Primary point gap :- .013" Contact breaker timing :- | | Make. | Break | |---|---|---| | A | -5° | 100° | | R | 55° | 160° | | | Retard | Aadvance. | |---|---|---| | Make | 57° | -3° | | Break | 161° | 101° | | Make | 233° | 173° | | Break | 339° | 279° | Range :- 60° Make ratio :- .583 (5) Automatic advance characteristics :- Hand range :- Auto range :- Total :- | Speed. | Degrees advanced. | |---|---| Contd. | ||