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).
'Phantom Springing' tests, concluding that stiffer front shock absorbers increase pitching and discomfort for rear seat passengers.
| Identifier | WestWitteringFiles\O\2January1926-March1926\ Scan152 | |
| Date | 10th March 1926 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c.c. to CJ. BJ. c.c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c.c. to DA.{Bernard Day - Chassis Design} EY. c.c. to Woz. ORIGINAL. Hs{Lord Ernest Hives - Chair}4/LG10.3.26. X8410\n̶X̶8̶5̶2̶0̶ PHANTOM SPRINGING. The recent tests made on springing have shewn that the riding comfort in the back seats is effected by alterations to the front springs. The manner in which we carried out the test was that we varied the load on the friction type front shock absorbers, this giving us roughly the effect of stiffer springs. It was proved that as the shock absorbers were made stiffer, the riding on the back seat was more uncomfortable. What one felt was not vertical accelerations, but pitching. These tests were made on a good average road at a car speed of between 20 and 30 m.p.h. We understand that it is under these conditions that complaints are being made. Apart from judging by personal discomfort, we made measurements by having in the car vessels filled with a measured quantity of water. These were carried by the passenger in a tray or placed on the floorboards. It was consistent that more water was lost with the stiff shock absorbers than with the slack shock absorber. We do not advocate slack shock absorbers; for all round average running conditions, we think the shock absorbers as at present adjusted are the best compromise. The point we wish to make clear is that the comfort on the rear seats at certain speeds can be affected by the front springs. Hs.{Lord Ernest Hives - Chair} | ||