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).
Providing guidance and qualifications for car springing charts across different models.
| Identifier | ExFiles\Box 106\1\ scan0139 | |
| Date | 27th August 1928 | |
| To Hm.{Capt. W. Hallam - Head Repairs} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} X5410 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}4/LG27.8.28. CAR SPRINGING. X8410 X7410 Herewith curves of car springs as requested. They are only approximations to enable reasonable springs to be put on a car without calculation. Naturally special cases like Summers or people requiring ultra-weak springs will have to be treated separately. Qualifications of the charts are :- PHANTOM. 40/50 REAR. Light springs, under 4" buffer clearance. Average, about 4.125" buffer clearance. Continental, about 4.5" buffer clearance. For old ladies you have been using 3" buffer clearance, but really we find that, as long as the springs are free and well greased, the springs we have shewn as weak give as good riding as any. 40/50 FRONT. Light. For all ordinary conditions the springs shewn by the line marked 'Light' should be used. Normal. Should be used when customers complain of hitting the buffers. Continental. If people are going to frequent the Continent, it pays to give them heavy front springs as it eliminates hitting the buffers in front and reduces breakage. This X line we believe approximates to Paris practice. 20 HP. REAR SPRINGS. Heavy, line approximates to 3.6" buffer clearance. This is quite adequate for all conditions including the Continent. contd :- | ||