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).
Graph plotting horsepower loss against speed for various new and worn tyres at a specific pressure and load.
| Identifier | ExFiles\Box 158\2\ scan0027 | |
| Date | 2nd May 1939 | |
| 6 TYRE LOSSES AT 44 LB/IN² CURVES AT FULL THROTTLE UNDER LOAD WEIGHT ON 2 TYRES TESTED 1920 LBS APPROX. H.P. LOST IN TYRES M.P.H. INDIA - NEW DUNLOP FORT NEW DUNLOP FORT WORN AVON - WORN DUNLOP TRACK RACING - NEW RM{William Robotham - Chief Engineer} / TAS{T. Allan Swinden} / 2-5-39 | ||