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).
Data sheet for a Packard rear spring, detailing load versus deflection measurements.
| Identifier | ExFiles\Box 127\1\ scan0090 | |
| Date | 23th March 1920 | |
| 23.3.20. PACKARD SPRING. (REAR) No.3 - with clips. Positive camber 5½ cwts. qrs. lbs. | Deflection. 4 2 21 | 1" 8 1 14 | 2" 12 1 0 | 3" 15 1 24 | 4" 18 3 20 | 5" 23 0 7 | 6" 26 0 0 | 6.500" | ||