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 to Zenith Carburetter Co. Ltd. regarding provisional settings for the Phantom III carburetter.
| Identifier | ExFiles\Box 122\2\ scan0029 | |
| Date | 22th May 1936 | |
| X1033 Exptl. Dept. Hs{Lord Ernest Hives - Chair}/Swdl.{Len H. Swindell}15/KW. 22nd May, 1936. The Zenith Carburetter Co.Ltd., Honeypot Lane, Stanmore, Middlesex. Dear Sirs, In reply to your letter of the 18th inst. with regard to confirmation of provisional setting for the Phantom III carburetter, there are several items which we wish to query, which are as follows. The main discharge jet as quoted in your list L.1048 does not convey its size etc., but the main discharge jet which was found satisfactory by your Mr. Fisher has a 28 bore .140" dia. throughout, is open-ended, and to our latest tests only requires one No.58 idle feed hole in the bottom of the discharge tube instead of the usual 4 holes. This is to be incorporated on future carburetters. Tests are also proceeding with regard to overcoming the loading up by reducing the bypass jet to .055" from .060" but at the moment is not finalised. The petrol level to be set at 5/8" from the floatchamber face under a head equivalent to a pressure of 3/4 lbs/sq.in. which is the pressure figure of the S.U. petrol pumps used by us on this car. Other than these few points the specification which you have endorsed is up-to-date as far as our tests have been carried out. Yours faithfully, FOR ROLLS-ROYCE LIMITED. | ||