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).
Test report on vehicle suspension performance, analyzing the effects of low-rating springs and various damping configurations.
| Identifier | ExFiles\Box 18\3\ Scan187 | |
| Date | 11th November 1930 guessed | |
| -3- all round, soft at low speeds; no pitching at the usual place, 35 to 45 m.p.h. the high speed riding was very good on all varieties of road in the district. Our previous experience with low rating springs has been that they tend to spoil the control of the car at high speeds, producing swaying, rolling and reducing the selectivity of the steering. On this car, however, after considerable testing, none of these faults were at all prominent, the car being very stable under all conditions, the steering very good. Before delivering the car, the Hartfords were removed at Sg{Arthur F. Sidgreaves - MD}'s request. The effect of removing the front friction damping is to slightly increase pitching. The buffer clearances with four passengers were Front N.S. 2.2" O.S. 1.8" Rear N.S. 3.75" O.S. 3.75" The spring alteration has lowered the front of the car by approx. .6" and raised the rear .5" The conclusions arrived at from these tests are that (1) Low rating front springs improve pitching in combination with (2) High hydraulic damping with drilled valves and (3) 15 lbs friction damping. | ||