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).
Comparison of rear spring deflection and buffer clearance between the 20 HP and 40/50 HP models.
| Identifier | ExFiles\Box 67a\1\ scan0068 | |
| Date | 1st January 1926 | |
| Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}/LG22.1.26. SPRINGING. The 20 HP. car rear springs under full load have a deflection of 5.125". This leaves the spring with a flat camber. The 40/50 HP. car rear springs under full load have a deflection of 6". This leaves the spring with a negative deflection of 1.00". Therefore if in each car the whole of the sprung weight were sprung for, one might expect the riding comfort to be similar. Actually the 40/50 HP. are sprung for only 3/4 of the sprung weight. The effect of this is that the cars are actually sent out with an 8" spring deflection for full load or 75% deflection greater than the 20 HP. The buffer clearance in this case is only 4.2". Hs{Lord Ernest Hives - Chair}/W.A.Robotham. | ||