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).
Test results for the deflection of front springs of a 20/25 model under braking torque.
| Identifier | ExFiles\Box 106\1\ scan0385 | |
| Date | 16th December 1935 | |
| 4546 Hs{Lord Ernest Hives - Chair}/Les.15/KW.16.12.35. Deflection of Front Springs of 20/25 under Braking Torque. 19-G-IV with standard low rating springs. Rear brakes off, front brakes on. Initial spring deflection = 4". Load lbs. N.S. Axle Twist Rear Spring O.S. Axle Twist Rear Spring N.S. Movement of axle backwards O.S. Movement of axle backwards 0 (0°-20' forwards) 0 (0°-25' forwards) 0 0 0 250 0°-20' 0°-15' - - 500 0°-30' 0°-25' 1/32 1/32 750 0°-40' 0°-35' + - 1000 0°-50' 0°-45' 1/16 1/32 21-G-IV with extra low rating Firth's No.172 springs. Initial spring deflection = 5.5". 0 (1°-20' Backwards) 0 (0°-50') 0 0 0 250 0°-20' 0°-5' 0 0 500 0°-35' 0°-20' - - 750 0°-45' 0°-30' - - 1000 1°-0' 0°-50' 1/16 1/16 1250 1°-5' 1°-0' Hs{Lord Ernest Hives - Chair}/Les.{Ivan A. Leslie} - | ||