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).
Design information memo detailing results from a 15,000-mile test on a new Bentley, focusing on steering and suspension.
| Identifier | ExFiles\Box 133\4\ scan0030 | |
| Date | 13th May 1935 | |
| x4703 To E.{Mr Elliott - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}10/KW.13.5.35. Design Information from 5-B-IV. So far we seem to have obtained the following information from the 15,000 miles test at present running :- (1) Contrary to general expectations and geometry, Hancock gets better results with regard to steering shocks with the springs shackled at the rear. This is a considerable relief to us because it gives good axle control with a minimum of complication. We should therefore recommend that in the specification for the new Bentley this should be included. (2) We have for some time been trying to run a Peregrine column on the Bentley with a view to saving weight. We have never been very satisfied with the results obtained, and Hancock now points out that the column movement is probably the worst feature. He says that the column whips from the thrust race upwards. We think that we could definitely use the Peregrine steering on the Bentley if (1) the helix angle on the worm and nut was dropped slightly to allow for the steering ratio, (2) a modification was made to reduce the whip in the steering column. We have already done a certain amount of work on this by stiffening up the shaft etc., and think it is worth completing the job for our new Bentley car. We are of course following on with a Marles type box, but this is an unknown quantity. (3) Thick Leaf Road Springs. Hancock seems now to have established the fact that leaf friction can be replaced by damping. He and Sr. are also quite emphatic that controllable dampers are wasted on the Bentley. We must say that we entirely agree. This rather calls for a new damper design with an adjustment on the damper, the whole unit to be smaller than at present in the ratio of the Phantom to the Bentley size. We appreciate that this may have to wait its turn owing to other more pressing commitments. | ||