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).
The 40/50 HP steering system, detailing modifications to the axle control lever and comparing spring deflection schemes.
| Identifier | WestWitteringFiles\S\March1928-May1928\ Scan184 | |
| Date | 1st May 1928 | |
| DA.{Bernard Day - Chassis Design} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/RmL/LG14;5.28. 40/50 HP. STEERING. X7430 / X450 X8450 With reference to DAA/Mll.5.28. Columns 6 and 7 are correct for Fz. series as on this series axle control was brought in. A 9.5" lever was fitted to 14-EX with the axle control damper, the clearance being almost negligible, this has since been changed for a 9.225" lever so that this figure should be corrected. With reference to the side steering tube end on 14-EX F.76108. This was a scheme got out to increase the deflection of the springs in the side steering tube and utilise existing parts which had been made for the old 3500 lbs. rating springs. The springs have a total of .400 travel and a rating of 1400 lbs/1". The scheme was replaced by N.sch.2258 giving .500 movement in either direction. Our views at the present moment on these two schemes are as follows:- .400 travel takes care of any road shocks likely to be encountered in England and on good Continental roads. It will not dissipate the shocks produced by large pot holes taken at speed, or the reactions one gets when passing anything on a French road, because only the crown is usually in good condition. When the springs reach the end of their travel and come up solid, the effect is most unpleasant and the driver often gets his knuckles rapped. The main advantage of the .400 travel is that it gives better car control contd :- | ||