Modifications to suspension and steering geometry for the B.III model and the first Silver Wraith.
| Identifier | ExFiles\Box 100\1\ scan0182 | |
| Date | 29th August 1938 | |
| 446 also 450. To Da. {Bernard Day - Chassis Design} from Ev. {Ivan Evernden - coachwork} c. to By. {R.W. Bailey - Chief Engineer} Hm. {Capt. W. Hallam - Head Repairs} c. to Rm {William Robotham - Chief Engineer} /FJH. {Fred J. Hardy - Chief Dev. Engineer} c. to Da {Bernard Day - Chassis Design} /Ev {Ivan Evernden - coachwork} /DB. {Donald Bastow - Suspensions} Da {Bernard Day - Chassis Design} /Ev. {Ivan Evernden - coachwork} 8/N.29.8.38. Re: Modified Suspension & Steering Geometry, B.III. -------------------------------------------- We understand that on B.III. the rubber sphere on the torque arm has been dropped on the average .375" in order to centralise the top of the yoke piece in the upper triangle outer bearing under static load. The intial backward set of the yoke equals approximately the forward deflexion of the latter under load. It is proposed to add .200" to the base of the sphere housing and to make up the rest by an adjustable die cast aluminum packing, the thickness of which will have to be determined when erecting each chassis by loading it up. This dropping of the torque arm sphere causes the cross steering tube to foul the top of the torque arm, and it is suggested that the outer end of the cross steering tube be dropped .250". On PD.254 herewith we shew this modification applied to the lever for improved steering geometry PD.199. For B.50 a new yoke piece is used PD.251 increasing the track to 58.500". The effect of this will be to increase the clearance between the cross steering tube and the hole in the torque arm. The yoke piece has been strengthened to deal with the increased loads resulting from the greater overhang of the pivot from the yoke, and the greater car weight. We believe the lever on the wheel can be that for B.III. and still clear the 7" section tyre. When we come to the first Silver Wraith a scheme for the suspension of which is shewn on PD.229 ( 2 sheets), the B.III. modifications should be applied. Here again, since we have decided to fit nothing greater than 7" section tyres the B.III. lever on the wheel should suffice. Cont'd. {John DeLooze - Company Secretary} | ||
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).