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 the development and performance of a vaporizer scheme and pilot jet, referencing issues with collector rings.
| Identifier | ExFiles\Box 75\2\ scan0271 | |
| Date | 5th October 1921 | |
| X2758 CC Mr. Belnap Mr. Nadin Mr. Caswell ROLLS-ROYCE OF AMERICA, INC. SPRINGFIELD, MASS. Oyl - G 51021 Oct. 5, 1921 Dear Hives: Replying to yours Hs{Lord Ernest Hives - Chair}/IG20.9.21, the following is our position at the moment on the subject you raise: 1. Vaporizer Scheme: We are very pleased with this, but have not yet achieved as complete success with the collector rings as you seem to have done. The absolute refusal of the car to load-up with the collector rings is a strong point in its favor, but we find that it knocks five miles an hour off the maximum speed and adds four seconds to the time for acceleration from 10 to 50 miles an hour. Without collector rings, acceleration from 10 to 50 miles takes twenty-one seconds, and with collector rings twenty-five seconds. The two forms of collector rings which we have so far used are shown by the enclosed prints XA-1271 and XA-1289. The second scheme is designed to obstruct the inlet bends less than the first, but does not appear to achieve this. We find that for practical purposes the vaporizer scheme without collector rings is a great improvement, and until we can find some means of collecting without interfering with the acceleration of the car, I think we had better not use the collector rings. The condition of the engine with the collector rings after a cold start is better than without the collector rings; but the condition of the engine after three thousand miles without collector rings was so good as to make us feel that this is a distinct forward step which should be taken at once, whereas the collector rings should be developed by further experiment. 2. Pilot Jet: We have achieved no permanent success with the pilot jet. In warm weather, the first scheme brought over by Mr. Platford was satisfactory, but on a cold morning it does not develop enough horsepower to push the engine around. We have attempted | ||