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 discussing a paper by G. B. Dorris on manifold design aimed at eliminating crankcase dilution.
| Identifier | ExFiles\Box 50\3\ Scan077 | |
| Date | 24th May 1921 | |
| 14305 Oy9 - G 24521 May 24, 1921 Mr. Claude Johnson, Managing Director, Rolls-Royce Ltd., London, England. Attention: Mr. Hives. Dear Sir:- X4390 14305 Re: Eliminating Crankcase Dilution, by G. {Mr Griffiths - Chief Accountant / Mr Gnapp} B. Dorris I enclose copy just received of a paper to be read by G. {Mr Griffiths - Chief Accountant / Mr Gnapp} P. Dorris at the forthcoming summer meeting of the S.A.E. which I think will be very interesting to Mr. Hives and possibly to Mr. Royce. It will be noticed that Mr. Dorris first of all shows a drawing of an upward sloping manifold of the type used on most American cars at the present time. This manifold has a hot spot at the Tee in the manner recommended by us and used on many American cars. Mr. Dorris gives the date of this manifold as about 1917 to 1919, but states that it is not satisfactory to take care of existing gasoline, presumably because the heavy ends are washed into the cylinder in starting. You will notice he collected fuel of .80 specific gravity in the bottles at either end of this manifold when starting up while he was using .70 specific gravity fuel in the carburetter. His improved manifolds have downward sloping branches to the ports, although they approximate to present practice in being as short as possible and having a vertical delivery pipe from the carburetter. Each of the downward sloping bends in the inlet pipe is provided with a pocket as a means for collecting gasoline with an idea eventually of passing this gasoline back into a hot spot above the carburetter. From the photographs, he still collects a large amount of liquid fuel at the bends. | ||