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).
Issue of 'booming bodies' in limousines, potential solutions, and the impact of the turbulent head.
| Identifier | ExFiles\Box 19\7\ Scan125 | |
| Date | 12th November 1928 | |
| Hs.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} c. to BJ. SG.{Arthur F. Sidgreaves - MD} c. to DA.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} c. to BY.{R.W. Bailey - Chief Engineer} C. c. to PN.{Mr Northey} CWB. x790 RL/M12.11.28. BOOMING BODIES - TURBULENT HEAD X.790 AND COMPRESSION RATIO. X.7830 X.8830 X.5830 I have enquired into the question of the booming limousine which, through being defective, was not available at the Show, and find that it is a type of body which is generally considered extremely difficult to get silent, so much so that the original metal top was cut out and replaced by leather. It may be understood that this did not entirely cure the trouble. I have already suggested that this type of body be tried on an underframe with rubber mounting. I am now suggesting that in our standard instructions to salesmen we ought to point out that this is a type of body which will probably give the owner much less satisfaction than a type of limosine in which the whole of the upper work is covered with leather or fabric. I feel sure that no sensible buyer would insist upon having a type of body if it were well known and admitted by the coachbuilders to be a definitely noisy body on all kinds of chassis, and until we have found a design which avoids the trouble we should ende-avour to persuade buyers to have some other type. There is not the sligtest doubt that body noises are, and naturally will be, the most difficult and most noticeable defects that are likely to spoil the reputation of a car. Bodies which are naturally not of a silent construction will be noisy from road vibrations. However, as far as I know there is not a shadow of a reason why the turbulent head should give greater vibrations, unless the compression is different, but this is not so, as proved by the absence of increase in HP. Hence, either it is a bad body for noise (which I believe), or Sales are hypercritical, however free the chassis is from vibrations. Therefore it would still be desirable to have bodies which are fundamentally silent, even if we had no engine and gears on the chassis. R.{Sir Henry Royce} | ||