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).
Investigation of a persistent 'booming' noise in a 20 HP car and requesting an experimental exhaust system for testing.
| Identifier | ExFiles\Box 48\4\ Scan222 | |
| Date | 26th September 1924 | |
| X4238 S/W {Sales / Derby Works} (Hs {Lord Ernest Hives - Chair} ) - copy to EP. {G. Eric Platford - Chief Quality Engineer} CWB28/LH {Mr Haworth} 26.9.24. I am now investigating a case of a 20 H.P.car - G.F.37, The Dowager Lady Cain, which is a bad 'Boomer'. The booming is not of the normal type, in that the sound does not 'come-on' and 'go-off' according to the engine revolutions or other variables, but is always present with slight variations in intensity. From a series of tests made, I believe that the primary cause is the Exhaust system, and a change in the swan-neck to one of a smaller diameter has made an appreciable difference in the general characteristics of the booming, and has, in fact, altogether improved the car, but has not removed the booming. I understand that you have now at the Works an Experimental Exhaust system which is a considerable improvement on the standard in this respect, and would very much like to have the opportunity of trying this on this particular car, which clearly resonates to the approximate note of the exhaust boom, to find out whether this will cure the trouble, or further ameliorate it. If, therefore, you can do so, will you please forward the essential parts of this Experimental Exhaust system to Cricklewood, by passenger train, tomorrow, for the purpose of this test, after which they will be returned to you immediately. This would appear to be a chance to make a very valuable experiment on this particular question. CWB. [Signature] 25/9/24 | ||