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 and contact breaker timing.
| Identifier | ExFiles\Box 48\3\ Scan085 | |
| Date | 11th August 1930 | |
| S.R. 253a (100 T) (S.H 159. 11-8-30) G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 -6- Contd. (2d') Platinum point gap :- .010" Contact breaker timing :- Table 1: Make. Break. A. {Mr Adams} +16.5 95.5 R. {Sir Henry Royce} 64 141.5 Table 2: Retarded. Advanced. Make. 64° +16° Break. 141° 94° Make. 244° 197° Break. 322° 273° Make ratio :- .435. (21a) Platinum point gap :- .006" Contact breaker timing :- Table 3: Make. Break. A. {Mr Adams} +16 97.5 R. {Sir Henry Royce} 63.5 144 Table 4: Retarded. Advanced. Make. 63° +16° Break. 143° 99° Make. 244° 196° Break. 325° 276° Make ratio :- .450. Contd. | ||