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).
Springing issues and experiences with the 20 HP car, comparing front and rear springs.
| Identifier | WestWitteringFiles\S\June1928-August1928\ Scan101 | |
| Date | 23th July 1928 | |
| Hs{Lord Ernest Hives - Chair}/RnL/LG23.7.28. SPRINGING. With reference to CWB3/GM20.7.28. The situation from our point of view is as follows :- 20 HP. CAR. Complaints of 20 HP. springing from customers are a rarity. We understand from the Repair Dept. that they have at least 20 complaints on the Phantom to one on the 20 HP. Our experience has been :- CONTINENTAL FRONT SPRINGS. Originally the 20 HP. front springs had 2.5" initial deflection. These springs broke continually in France and have given trouble ever since. A proposition is being put forward at present to change them all free of charge. The present standard front spring has 2" initial deflection. If we use any less than the normal buffer clearance of 1.950" we hit the buffers very frequently on bad roads - (See daily reports last 10,000 miles test 10-G-lll 19.4.27/29.4.27) even with this stiff type of spring. 10-G-lll had front springs 50 lbs; lighter than those required to give 1.950" buffer clearance. REAR SPRINGS. On the rear the normal buffer clearance is 3.65". We find that 3" is about the minimum we can use on the Continent. 10-G-lll had 900 lbs; rear springs which gave more than the normal 3.65" buffer clearance with four passengers. The obvious way to enable more flexible springs to be fitted is to reduce the buffer clearance. As, however, we broke both front and rear springs during these tests we hesitate to increase the stresses further by utilising greater deflection. BRITISH CONDITIONS. Though the 20 HP. suffers infinitely less than the 40/50 HP. from the 20/30 m.p.h. joggle on good roads, we have had cars where this feature is somewhat pronounced. In our experience, weight distribution and rear shock damper setting has the greatest influence on the phenomena. Weak rear springs and low tyre pressure, while making an enormous improvement over really bad roads, have always disappointed us on this particular complaint. Summarising the position :- contd :- | ||