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 Humber Ltd. inquiring about engine timing diagrams and carburation difficulties.
| Identifier | ExFiles\Box 126\2\ scan0034 | |
| Date | 11th July 1936 | |
| TELEPHONE 5041 COVENTRY. TELEGRAMS: HUMBER, COVENTRY. HUMBER LTD. COVENTRY. July 11th, 1936. W.A.Rowbotham Esq., Messrs.Rolls-Royce Ltd., DERBY. Dear Mr.Rowbotham, In talking over matters of carburation, particularly in connection with the difficulty of obtaining really good idling on a modern engine, a man who is generally speaking a very sound fellow on these matters mentioned to me that on your new engine you have had so much difficulty in obtaining good idling that you have actually gone to the extent of arranging a 160° blind spot in the timing diagram, as opposed to the slight overlap which most of us use, and that although you have admittedly sacrificed a considerable amount of power in the process you have actually found this an advisable move. Without asking you to disclose secrets which are in what we may call the "State" classification, I wonder whether you would be good enough to let me have the actual facts of the case? With kind regards, Yours sincerely, [Signature] S.S.Winter | ||