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).
Test results for a J Motor under cold and hot conditions, detailing electrical and rotational speed measurements.
| Identifier | ExFiles\Box 64\2\ scan0163 | |
| Date | 30th June 1928 guessed | |
| -2- 14-EX (4 3/4 : 1 Comp.Ratio). Ratio 13 : 1. COLD :- Volts 9.3 Amperes 123. Engine r.p.m. 90 Motor r.p.m. 1170 HOT :- Volts 10.10 Amperes 108 Engine r.p.m. 110 Motor r.p.m. 1430 } J MOTOR | ||