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).
Chart comparing the rear brake drum temperatures of a 4¼ Litre Bentley under icy conditions.
| Identifier | ExFiles\Box 85\1\ scan0036 | |
| Date | 14th January 1936 | |
| REAR BRAKE DRUM TEMPERATURE CHART 4¼ LITRE BENTLEY ROAD CONDITIONS: ICY ALL READINGS TAKEN WITH CAR STATIONRY. THERMOCOUPLES IN SMALL BRASS PAD SPRING LOADED AGAINST BRAKE DRUMS. WEAR OF FERODO DURING TEST:- MILLENITE DRUM: 5 HALF TURNS. ALUMINIUM DRUM: LESS THAN A HALF TURN. NEAR SIDE MILLENITE DRUM OFF SIDE ALUMINIUM- N.M. STEEL COMPOSITE DRUM TEMPERATURE - DEGREES CENTIGRADE MILES 660°F 35 MINUTES Route Annotations: TICKNALL HALT, ASHBY, TWYCROSS, FENNY DRAYTON, ROYAL RED GATE, LEVEL CROSSING, WATLING STREET. | ||