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).
Tests carried out to investigate and resolve engine spitting issues on car 22-EX.
| Identifier | ExFiles\Box 6\7\ 07-page105 | |
| Date | 20th November 1930 | |
| -3- He/AD.1/SL.20.11.30.Contd. are obtaining some more so that we can get further experience. So far on 22-EX. we can find no disadvantage. Bench tests are being carried out in parallel to confirm the metering characteristics. Further tests carried out, but from which so far no improvements or effect on spitting have been obtained are:- (1) The effect of a smaller dia. air valve diaphragm. (2) The effect of as large dia. an air valve diaphragm as it was possible to use. (3) Valve timing overlap cut out by running with (a) .020" inlet valve clearance. (b) .020" exhaust valve clearance. (4) The balance holes in the air valve dashpot were blanked up and replaced by four milled grooves on the inside diameter of the small bore of the dashpot. (5) Exhaust valve not closing. (6) Inlet valves not closing. All the above tests were carried out on a car 22-EX. on which spitting is very bad but no improvement or appreciable effect either way could be observed. We are continuing investigations. He/AJL. | ||