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 regarding the supply and specification of plugs for a 4.5-litre engine.
| Identifier | ExFiles\Box 162\4\ img137 | |
| Date | 11th March 1936 | |
| K·L·G Sparking Plugs Limited CONTRACTORS TO THE AIR MINISTRY, ADMIRALTY, WAR OFFICE & FOREIGN GOVERNMENTS. Sole Manufacturers of "KLG" Sparking Plugs, also Jigs and Precision Tools PUTNEY VALE, LONDON, S.W.15 Telephone Putney 2671. (Four lines) Telegrams: Kaelgee, Phone, London. PLEASE REFER TO TECHNICAL DEPT. AND QUOTE REFERENCE RGM/MSR. IN YOUR REPLY RS{Sir Henry Royce's Secretary} 11th March 1936. H.E. West Esq., Messrs. Rolls Royce Limited, DERBY. Dear Mr. West, I am very sorry you were away when I called yesterday for I wanted to discuss further with you the question of plugs for the 4 1/2 litre development engine. However, I saw Mr. Smith and Mr. Swindell and left with the latter 6 type 690 and 6 type 646 plugs. These have 12 m/m reach, and the 690 is precisely the same in heat and oil characteristics as the 828. Upon referring to the blue print of the cylinder head, we found that the length of thread in the plug hole was 17.5 m/m.{Mr Moon / Mr Moore} Therefore with a washer an 18 m/m reach plug would just about bring the mouth of the plug flush with the inside of the combustion chamber. It seems to me, therefore, that an 18 m/m reach plug with full thread would be correct for this particular head. So that you may carry out various carburation tests I arranged with our Works on the telephone to have despatched to you last night further supplies and the following plugs were sent - 6 type 731T-LR{Mr Ellor} 6 do 646T-LR{Mr Ellor} 6 do 689T-LR{Mr Ellor} 6 do 690T-LR{Mr Ellor} the "LR{Mr Ellor}" denoting long reach (18 m/m). [Logo: THE SOCIETY OF MOTOR MANUFACTURERS & TRADERS LTD] [Logo] | ||