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).
Technical memorandum detailing suspension data and spring rates for a Packard vehicle.
| Identifier | ExFiles\Box 127\1\ scan0289 | |
| Date | 1st May 1937 | |
| To H.{Arthur M. Hanbury - Head Complaints} from Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} c.to Da.{Bernard Day - Chassis Design} c.to Ev.{Ivan Evernden - coachwork} Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}1/BJ.1.5.37. Packard Suspension. The following data has been obtained concerning our Packard. Wheel movement. OS. NS.{Norman Scott} Bump 3 15/16th 4¼ Rebound 2¼ 2 11/16th Clearance between radius arms and cross steering tube - Lock OS. NS.{Norman Scott} Bump Right Zero Ample Bump Left Ample ¼" Rebound Right 7/16ths 9/16ths Rebound Left ¼" ¼" Effective Spring Rate. The spring rate in the normal position is 1" wheel movement per 100 lbs per side; but it takes 625 lbs per side to compress springs to full bump, the rate increasing very much the last 1". It will be noticed that although the Packard designers have only provided 2¼" rebound, the limitation has not been due to lack of clearance in their suspension. The car had never been on full bump, full lock as there was loose mud between radius arms and cross steering tube. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} | ||