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).
Suspension spring tests comparing different types and their effect on axle movement and road holding.
| Identifier | ExFiles\Box 20\2\ Scan059 | |
| Date | 31th January 1920 | |
| 2 Hsl/LG31.1.20. Contd. together, broke away, This immediately made a very big difference to the amount of side movement shown by the rubbing on the bottom leaf. The total amount of movement without the clip on was 1.0" compared with .5" with the clip on. We then changed the bottom leaf of the springs for some which have not been split. We found that immediately we put these on, the axle did not bounce nearly so violently. We measured the maximum amount the wheels jumped clear of the cam. XWe measured that with the solid springs it was 1.3" and with the split springs it was 3.5". In both of these test the shock absorbers were dis-connected. Not only was the axle steady over the solid springs but the frame itself was more steady. The results so far go to prove that the split rear springs certainly are not good for keeping the axle on the road. X.2650. Sometime ago we pointed out that we found that on a car with springs under the axle that the axle did not follow the road nearly so well as with similar springs above the axle. The conclusions we cam to at that time were that we could not afford to have the extra lateral flexibility which we get with the springs below the axle because owing to the weight of our axle the only way to keep it on the road is to take every advantage of the weight of the frame and the body to keep it down. It would appear that the first funda-mental thing to get a comfortable riding car is to do every-thing possible xxxxxx so that the axle will follow- the road Contd. OS/C D (ET'S) (IN G'N) A.S. (L OO!) F'C S/C S. H | ||