Brake performance, covering stopping distances and squeaking issues.
| Identifier | ExFiles\Box 7\7\ X 606 Brakes-page057 | |
| Date | 4th May 1937 | |
| -3- Stopping Distance. This is poor, 46 feet from 30 M.P.H. being recorded three times, as against about 36 feet on a 25-30 H.P. The brake ratio front to rear on Wraith is 1.065 as against 1.13 on a 25/30 H.P., whereas the axle weight ratio front to rear is 0.905 on Wraith and only 0.830 on 25/30 H.P. This varies slightly with different bodies. The Wraith brake ratio front to rear should be 1.25 which could be obtained by altering the linkage ratios from 23.4 to 25.5 on the front, and 16 to 14.6 on servo to rear. This will increase the pedal pressure to lock the rear wheels by 5% which can, if necessary, be restored by altering the servo cam angle. We suggest that N. schemes should be prepared in accordance with the above because the car will one day be tested by the Motor and Autocar people. Squeaks. We have had light brake squeaks using Ferodo P5 material; we think Ferodo ML is less likely to squeak, and we shall try it soon. We think it would be advisable to prepare designs for tipping shoes on all brakes, but we certainly do not want to use them if we can avoid it. RM {William Robotham - Chief Engineer} /AFM. {Anthony F. Martindale} | ||
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).