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 primary point gap, contact breaker timing, and automatic advance characteristics.
| Identifier | ExFiles\Box 40\2\ Scan068 | |
| Date | 17th December 1925 guessed | |
| -2- (4) Primary point gap:- .013" Contact Breaker timing :- Make. Break. A.{Mr Adams} 26° 104.5° R.{Sir Henry Royce} 85.5° 164.5° Retard. Advance. Make 85° 26° Break 165° 104° Make 266° 206° Break 344° 285° Range:- 60° Make ratio :- .437 (5) Automatic advance characteristics :- Hand range:- Auto range :- Total :- Speed. | Degrees | advanced. Contd. | ||