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).
Tyre tread print analysis for an 'India Speed Special' tyre.
| Identifier | ExFiles\Box 29\4\ Scan151 | |
| Date | 23th November 1933 guessed | |
| - INDIA SPEED SPECIAL- SIZE 5.50/18 (28x5.50) TOTAL AREA = 23.17 SQ. INS. ROAD CONTACT " = 16.27 " " GROOVE " = 6.9 " " SKID LINE LENGTH = 64 1/2 LOAD = 8 CWTS | ||