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 lost in various tyres against speed in miles per hour.
| Identifier | ExFiles\Box 158\2\ scan0023 | |
| Date | 2nd May 1939 | |
| 2 TYRE LOSSES AT RATED PRESSURES CURVES AT FULL THROTTLE UNDER LOAD. WEIGHT ON 2 TYRES TESTED 1920 LBS APPROX. DOTTED CURVES SHEW LOSSES AS GIVEN BY THE ANDREAU FORMULA HP. LOST IN TYRES M.P.H. INDIA 34 LB/IN² DUNLOP 33 LB/IN² MICHELIN PILOTE 27 LB/IN² ANDREAU 30 LB/IN² ANDREAU 44 LB/IN² DUNLOP TRACK RACING 44 LB/IN² | ||