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).
Alterations to a body sub-frame on a 20 HP car to reduce noise.
| Identifier | ExFiles\Box 41\3\ Scan442 | |
| Date | 15th December 1924 | |
| R.R. 493A (50m) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF:HS{Lord Ernest Hives - Chair}/TMW/LG15.12.24. REPORT ON BODY SUB-FRAME FITTED TO GF.68. 20 HP. On receipt of the above car from London fitted with a Landaulet Body, it was found that the front sub-frame supports had been altered. The rubber pads, as supplied from Derby, had been discarded and a series of fibre and rubber packings inserted instead, the latter being ¼" thick - fibre had also been inserted at the rear supports. We have not altered this, as when tried on the road it was thought to be excellent for general riding, and diminution of body noises, and decided to endeavour to set up, as near as possible, the conditions that would exist if the body was bolted to the main frame in the usual manner. This was accomplished by substituting metal for the rubber and fibre blocks - front and rear - introducing packing pieces between each sub-frame cross member and the main frame, the whole being bolted solidly together. In addition, distance pieces and bolts were inserted between the channels of the two frames, and brackets were fixed at the extreme front ends, thus giving lateral solidarity. It was possible to rapidly change about the conditions so that repeated comparisons over the same roads at the same speeds (designed to show by body noises) could be made. We do not think that this body could be made to boom badly as it happens, but it was possible to make it bad enough to show the difference, under the two conditions, to be most marked, particularly running over stone contd :- | ||