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).
Letter from K.L.G. Sparking Plugs Limited discussing the specifications and supply of various spark plug models.
| Identifier | ExFiles\Box 162\4\ img138 | |
| Date | 11th March 1936 | |
| K.L.G. Sparking Plugs Limited CONTINUATION NO. 2 DATE 11-3-36. H.E. West Esq., Messrs. Rolls Royce Ltd., So that the heat and oil characteristics of these plugs may be quite plain to you, I have pleasure in giving you a list of this range in order of heat and oil resistance. 875-LR{Mr Ellor} 731-LR{Mr Ellor} 689-LR{Mr Ellor} 646-LR{Mr Ellor} 690-LR{Mr Ellor} Without the letters "LR{Mr Ellor}" they have 12 m/m reach and with them 18 m/m reach. As particularly requested by you I have put in hand a dozen type 828 with 14 m/m full thread, but as these have to be made up specially there will be some delay and our factory cannot promise them before the 18th instant at the earliest. During these preliminary tests I would suggest that you carry on with our production plugs, and if eventually we find it necessary to make you a special type it can always be done when we know exactly what is required. I understand the engine is likely to be on the test bed for a week or so, and I look forward to the pleasure of calling upon you next week in order to learn exactly what is happening. I intended to send you six type 875T-LR{Mr Ellor} last night, but unfortunately we are completely out of stock. Half a dozen are in hand and we hope to despatch them to you to-night. Yours sincerely, | ||