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).
Performance data sheet for various friction materials from Ferodo Limited.
| Identifier | ExFiles\Box 141\3\ scan0246 | |
| Date | 29th January 1934 guessed | |
| From FERODO LIMITED. Chapel-en-le-Frith. Sheet No. 1 Pressure on discs lbs Torque lbs-ins Coefficient of friction FERODO B.Z. normal coefficient of friction 0.4 - 0.36 250 570 775 1130 270 630 900 1305 .27 .276 .29 .29 S. 3914 normal coefficient of friction 0.4 - 0.36 250 570 775 1130 252 585 900 1350 .26 .25 .29 .3 FERODO RAD. 5 normal coefficient of friction 0.4 - 0.36 250 570 775 1130 360 630 900 1188 .36 .276 .29 .26 VLM/20 normal coefficient of friction 0.35 - 0.28 250 570 775 1130 198 450 765 1125 .19 .2 .24 .25 FERODO M.Z. normal coefficient of friction 0.4 - 0.36 250 570 775 1130 225 450 810 1125 .22 .2 .25 .25 FERODO RAD.11 normal coefficient of friction, 0.4 - 0.32 250 570 775 1130 216 450 765 1080 .216 .2 .24 .24 RAD. 13 normal coefficient Of friction 0.38 - 0.3 250 570 775 1130 360 675 990 1485 .36 .29 .32 .32 FERODO FIBRE normal coefficient of friction 0.6 - 0.5 250 570 775 1130 360 675 1035 1305 .36 .29 .33 .25 FERODO FIBRE H.D. normal coefficient of friction 0.55 - 0.5 250 570 775 1130 315 675 1125 1485 .31 .3 .36 .32 FERODO M.R. normal coefficient of friction 0.43 - 0.39 250 570 775 1130 270 585 810 1215 .27 .25 .29 .27 | ||