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 detailing secondary milliamps, contact breaker point gaps, and timing data.
| Identifier | ExFiles\Box 43\4\ Scan247 | |
| Date | 18th February 1930 guessed | |
| -5- (15) Secondary milliamps :- Maximum :- 5.0 Minimum :- 3.0 (16) Contact breaker point gap. .017" Contact breaker timing. Retard. Advance. Make. 47° 16° Break. 84° 54° Make. 135° 104.5° Break. 174.5° 144° Make. Break. A 15° 54° R 46° 84° Make ratio :- .428. Contact breaker point gap :- .009" Contact breaker timing:- Retard. Advance. Make. 41° 10.5° Break. 90° 60° Make. 130° 99.5° Break. 181° 151° Make. Break. A 10° 60.5° R 40.5° 90.5° Make ratio :- .558. Average variation in break :- 6.5° Compared with 2 spark per rev. magneto = 3° contd. | ||