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).
Tendency to misfire on high compression 20/25HP engines and recommending a smaller spark plug gap.
| Identifier | ExFiles\Box 58\1\ Scan170 | |
| Date | 30th May 1930 | |
| Hs.{Lord Ernest Hives - Chair} from Mx.{John H Maddocks - Chief Proving Officer} X5970 Mx{John H Maddocks - Chief Proving Officer}3/T30.5.30 Sparking Plugs - High Compression 20/25HP We find on test that there is a tendency to misfire picking up. We find it an advantage to use a plug with a gap of .020 instead of .025. Will you please let me have your views on the matter. 17 GW running with .020" gap. Mx{John H Maddocks - Chief Proving Officer} | ||