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 showing spring poundage for various body weights for the Wraith model.
| Identifier | ExFiles\Box 9\5\ 05-page212 | |
| Date | 19th May 1938 guessed | |
| WRAITH SPRING POUNDAGE FOR VARIOUS BODY WEIGHTS SPRING POUNDAGE REAR OFFSIDE FRONT NEAR SIDE FRONT WEIGHT OF BODY IN CWT. 1300 1200 1100 1000 900 11 12 13 14 | ||