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).
Comparing clutch thrust pressure and finger ratios between Borg & Beck and Long clutches.
| Identifier | ExFiles\Box 130\3\ scan0035 | |
| Date | 16th December 1938 | |
| 1110 To By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Da{Bernard Day - Chassis Design}/Hdy.{William Hardy} Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler}8/JH.16.12.38. re Clutch Thrust Pressure. Borg & Beck & Long. With reference to memo. Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler}1/JH.30.11.38., it may at first appear somewhat paradoxical that the thrust (when withdrawn) on the withdrawal bearing of the 10" Long clutch, which has lighter thrust springs, is more than that of the 10" B. & B. The reason however is that the Long has a finger ratio of 4 . 73 as compared to 5.5 for the B. & B. consequently the ratio of the linkage between the pedal and the withdrawal bearing should be correspondingly modified in order to get the best results from the Long clutch, and this is fully dealt with on the pedal mechanism analysis chart Rm.{William Robotham - Chief Engineer}567. Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler} | ||