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).
Specification sheet for ignition timing, primary point gap, and advance characteristics.
| Identifier | ExFiles\Box 40\2\ Scan095 | |
| Date | 29th March 1926 guessed | |
| -2- Contd. (4) Primary point gap :- Average = .013" Contact breaker timing :- Retard. Advance. Make 47° -11° Break 156° 98° Make 228° 169° Break 336° 278° -11-109-98° Make Break. A -11° 198° R 47° 156° 47°-109°-156° Range:- 58° Make ratio :- .605 (5) Automatic advance characteristics :- C Speed. Degrees advanced. Hand range :- Auto range :- Total :- Contd. | ||