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).
Hispano servo motor, detailing performance data after restoration.
| Identifier | ExFiles\Box 22\1\ Scan165 | |
| Date | 29th April 1924 | |
| R.R. 493A (20H) (D.A. 652 20-3-24) J.H.D. 1559 Expl. No. 4214 REF: Hs{Lord Ernest Hives - Chair}/ACL/LG29.4.24. EXPERIMENTAL REPORT. HISPANO SERVO MOTOR. It was found after previous tests on this servo that the braking on the car was not up to its usual standard. The output of the servo has now been restored to normal by carefully bedding the lining and 'running in' on the road. The following figures give the output of the servo working with its normal efficiency :- | Eqvt. pedal pressure. | Torque input. | Total torque output. | Torque given by servo. | Total T.output / Torque input. | |---|---|---|---|---| | lbs. | | | | | | 12 | 144 | 867 | 723 | 6.0 | | 18 | 216 | 1610 | 1394 | 7.5 | | 24 | 288 | 2290 | 2002 | 7.9 | | 30 | 360 | 2790 | 2430 | 7.7 | | 36 | 432 | 3160 | 2728 | 7.3 | | 42 | 504 | 3410 | 2906 | 6.8 | | 48 | 575 | 3560 | 2985 | 6.2 | | ||