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).
Front brake system performance and mechanical efficiency.
| Identifier | WestWitteringFiles\K\December1923\ Scan69 | |
| Date | 12th July 1923 | |
| R.R. 403A (40 H) (SL 42 12-7-23). J.H.D. EXPERIMENTAL REPORT. Expl. No. 9940 REF: HH/ADLTC.12.23. Front brake equaliser (locked) Pressure distributor (servo connection locked) w = pressure applied at brake cam levers on front brakes (equivalent to w/2 lbs. at each cam lever). W = pressure at pedal lever on distributor overcome by (w) Leverage on this car found to be as 1 : 1.45 (i.e. W x 1 = w x 1.45). These tests are the converse of tests on page 1. | w lbs. | W lbs. | Theor: W (w x 1.45) | Loss of W to friction. | Mech. effcy: | |---|---|---|---|---| | 57 | 50 | 82.65 | 25.65 | 60.5% | | 78 | 75 | 113.1 | 38.1 | 66.3% | | 98 | 100 | 142.1 | 42.1 | 69.3% | | 128 | 125 | 185.6 | 60.6 | 68.7% | | 145 | 150 | 210.25 | 60.25 | 71.3% | | 172 | 175 | 249.4 | 74.4 | 70.3% | | 198 | 200 | 287.1 | 87.1 | 69.6% | | 226 | 225 | 327.7 | 102.7 | 68.75% | | 250 | 250 | 362.5 | 112.5 | 69% | | 273 | 275 | 395.85 | 120.85 | 69.7% | | 297 | 300 | 430.65 | 120.65 | 69.7% | | 320 | 325 | 464 | 139 | 70.25% | | 333 | 350 | 482.85 | 132.85 | 72.5% | Mechanical efficiency (average). = 68.4% | ||