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).
Table detailing the effective running radius of various tyres at 90 m.p.h.
| Identifier | ExFiles\Box 157\6\ scan0169 | |
| Date | 24th September 1937 | |
| 24th September, 1937. EFFECTIVE RUNNING RADIUS AT 90 m.p.h. Rim. Load. Inflation Pressure. Eff. Radius. 5.50/18. 3.25" 10 cwts. 30 lbs. 14.72". 6.50/16 4.50 D.{John DeLooze - Company Secretary} 10 cwts. 30 lbs. 14.21". 6.50/16 5.00 E.{Mr Elliott - Chief Engineer} 10 cwts. 30 lbs. 14.31". ----oOo---- | ||