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).
Use of porcelain versus mica spark plugs in Bentley cars.
| Identifier | ExFiles\Box 88\1\ scan0242 | |
| Date | 21th July 1936 | |
| S/W. To Rm.{William Robotham - Chief Engineer} from Sg.{Arthur F. Sidgreaves - MD} Re: Bentley Cars and Sparking Plugs. You mentioned the other day, I think, that in America, where they all run on leaded fuels, they use a porcelain plug as distinct from the mica plug prevalent in this country. I understand that the Champion plug is porcelain, and somebody was telling me the other day that Humbers use these on all their cars and have found K.L.G's no good on their engines. I am just mentioning this as I was wondering what experi- ence we have had with Champion plugs. Sg.{Arthur F. Sidgreaves - MD} | ||