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).
Removing the outside spark plug on the Phantom engine and improving plug accessibility on the 4-port head.
| Identifier | ExFiles\Box 93\2\ scan0179 | |
| Date | 12th January 1937 | |
| -308, Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} from Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}6/R.12.1.37. We contemplate doing away with the outside plug on the Phantom engine. In our experience it gets fouled the more easily of the two, and we consider that one plug per cylinder is quite enough on a 12-cylinder engine. Will you please go over the 4-port head, and ensure that the plug position is as accessible as it can be. We believe that some of the plugs were originally put in at an angle to suit the 4-port scheme, and now that we have the Stromberg carburetter their position can be improved. Rm.{William Robotham - Chief Engineer} | ||