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).
Modification to Ph.II Controllable Dampers by adding grooves to the pistons to improve ride quality.
| Identifier | ExFiles\Box 16\5\ Scan192 | |
| Date | 19th June 1934 | |
| X7520 R/B - C. c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to Ed.{J. L. Edwards} c. to Hd.{Mr Hayward/Mr Huddy} c. to Dy.{F R Danby} Ph.II Controllable Dampers. We have recently made a modification to our production controllable dampers which largely improves the riding qualities of our cars, by reducing the pitching. This has been done by putting grooves in the top of the damper pistons, which revents an oil pressure building up, and in consequence prevents loss of efficiency of the dampers. Although the dampers which are now being produced have this improvement, we have taken no steps to modify the 150 chassis which are already built without grooves in the pistons. The first move appears to be to modify our Trials Cars, so that prospective customers may have runs in cars under favourable conditions, and also so that you can try this improvement on various cars to see if it is worth altering chassis which are already built. Up to the present there has been some fairly severe criticism against cars with low rating springs and controllable dampers. Grooves in the pistons are bound to alter people's opinion on this very important subject. There are no parts scrapped in effecting this alteration, the cost being purely that of removing and dismantling the dampers, so that the grooves can be added. We suggest that M.{Mr Moon / Mr Moore} should remove the dampers from the Trials Cars and send them to W. for the grooves to be added. We can see no possible reason for any trouble being caused from the addition of grooves, as it only ensures that the dampers will continue to do the work for which they are designed. Actually we have had a great deal of road and bumper experience with grooves in the pistons. There is a Standardisation Sheet at present in circulation. Hs{Lord Ernest Hives - Chair}/ I.A.Leslie. | ||