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 comparing plug voltage at different plug gaps and water temperatures.
| Identifier | ExFiles\Box 37\1\ scan 187 | |
| Date | 5th December 1930 guessed | |
| W863 contd (3) 4 7800 5 6200 6 5920. Average max voltage per plug 6015. b) Plug gaps .025" Water temp' 95 to 100°C Cylinder No. Plug voltage 1 5300 3 6020 6 4700 c) Plug gaps .030" Water temp' 70°C Cylinder No. Plug voltage 1 4700 2 4820 3 6600 4 6020 5 5920 6 7650 Average max. voltage per plug 5950. d) Plug gaps .030" Water temp' 95 to 100°C Cylinder NO Plug voltage 1 3900 3 5300 6 5400 These results show that the plug voltage with '.025' and '.030' gaps is about the same. We can only explain this by the fact that the gap setting was very critical and that the plugs in the '.030' case may have been hotter. With the plugs | ||