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).
Comparing the weights of wheels and tyres for various car models.
| Identifier | ExFiles\Box 124\3\ scan0344 | |
| Date | 19th May 1935 | |
| 19.5.35. Top Table: | Vulture 6.50 x 18 | Vulture 7 x 18 | SpectreCodename for Phantom III 7.50 x 17 | 20/25 6.00 x 19 | 20/25 Projected 6.00 x 17* | | Wheel & Tyre Weights - lbs. | 64.25 | 73.25 | 69.00 | 64.0 | 61.25 | Bottom Table: | Bentley 6.50 x 18 | Projected Bentley 6.25 x 16 | Buick 6.25 x 16 | Graham 7 x 16 | Essex 6.25 x 16 | | Wheel & Tyre Weights - lbs. | 50.62 | 45 approx | 46.25 | 53.375 | 43.125 | | ||