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).
Detonation tests on a Bentley car to determine the correct automatic advance curve.
| Identifier | ExFiles\Box 82\4\ scan0282 | |
| Date | 7th April 1936 | |
| To E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} c. to Wst. X 200 Hs{Lord Ernest Hives - Chair}/Wym.{G. Harold Whyman - Experimental Manager}20/KW.7.4.36. Bentley Detonations. We have been carrying out detonation tests on Bentley car B-23-AH with a de-turbulated cylinder head supplied by Hs{Lord Ernest Hives - Chair}/FD{Frank Dodd - Bodies}, with a view to obtaining the correct curve for automatic advance. The automatic portion of the governor was cut out and the amount of advance required was determined by advancing the ignition hand control to detonation point at different speeds. It was found that detonations were only audible up to 47 m.p.h. and above that speed the degrees of advance were governed by engine roughness. Herewith attached curve showing automatic advance required to keep engine free from detonations up to 47 m.p.h. and to retain engine smoothness at higher speeds. Hs{Lord Ernest Hives - Chair}/G.H.Whyman. | ||