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).
Technical memorandum discussing the testing and performance of controllable shock dampers on a 40/50 HP car.
| Identifier | ExFiles\Box 151\2\ scan0163 | |
| Date | 25th January 1934 | |
| To Sg. {Arthur F. Sidgreaves - MD} from Hs {Lord Ernest Hives - Chair} /Les. X4698 c. to Nor. c. to E. {Mr Elliott - Chief Engineer} c. to By. {R.W. Bailey - Chief Engineer} c. to EP. {G. Eric Platford - Chief Quality Engineer} c. to Mr. c. to Em. Controllable Shock Dampers. 40/50 HP. Last Monday we were able to try the first complete production car with controllable dampers. This car had standard rating road springs. We were pleased with the behaviour of the car, the dampers being very effective and the comfort in the rear of the car was very good. The improvement to steering road shocks was very noticeable. When the hand control is moved over to maximum, the soft riding was reasonably comfortable with very little pitching. The next day experience was gained with Sg {Arthur F. Sidgreaves - MD} 's car, 104-MY, having reduced front damper loads. Production maximum loads are 400 lbs. front and 300 lbs. rear. On our car 22-EX we have effected an improvement in the riding qualities of the car by reducing the front damper loads to half; namely, 200 lbs. Recently we made a similar modification to 104-MY. From the tests made last Tuesday it is obvious that 104-MY requires more load on the front dampers to prevent pitching than our car 22-EX. This is possibly due to the differences in bodies, but we are more inclined to suspect that the road springs are becoming dry on 22-EX. This car has done 15,000 miles with scarcely any attention owing to the rush on developing our dampers. We have now fitted a pair of front dampers to 104-MY giving a maximum load of 250 lbs. Although the tendency for pitching is reduced, we feel that certain customers may want more front damping. We should like to have criticisms from London concerning this car. Under these circumstances we are not in favour of reducing the front damper loads on production cars until we have tried more finished cars with the present loads, and carried out further tests on 22-EX after the road springs have been dismantled. If the finished cars are satisfactory we should recommend that no alteration be made until 22-EX has completed 10,000 miles. Hs {Lord Ernest Hives - Chair} /I.A.Leslie. | ||