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).
Outlining proposals for further suspension experiments on 20HP and Phantom models.
| Identifier | WestWitteringFiles\O\April1926-June1926\ Scan10 | |
| Date | 10th April 1926 | |
| TO HS.{Lord Ernest Hives - Chair} FROM DA.{Bernard Day - Chassis Design} ORIGINAL SUSPENSION EXPERIMENTS. X8410 X9410 X5410 X235 This is to confirm one or two points on which it was intended to make further experiments - (1) To find out whether the 20HP. is more sensitive to modifications to the rear suspension than the Phantom, by getting some stiffer rear shock damper springs for the former, and increasing the shock damper load on the rear. In connection with this same point it does seem worth while to see whether one could spoil the 20HP. by altering the rear in the same way that it was spoiled by altering the front - for instance, supposing the shock dampers were left off the front altogether, and the rear varied in stiffness. We suggest also that it might be worth while doing this on the New PhantomCodename for PHANTOM I and the Silver Ghost. (2) You were going to try the riding of an old 20HP. chassis without front wheel brakes in view of the fact that the 20HP. front springs have been stiffened 25% (instead of 12 1/2% in the case of the New PhantomCodename for PHANTOM I) and one would think would have made a definite difference. (3) It is pointed out that the EAC.1. chassis has 48" springs with a 4" initial deflection. If the brake system could be made the same as standard New PhantomCodename for PHANTOM I it should be possible to get an idea of what would be the value of lengthening the front springs on the standard chassis as regards enabling a more flexible suspension to be used without an increased tendency to turn the axle over. We propose sending some suggestions to R.{Sir Henry Royce} on this point. (4) It was seen that stiffening up the shock dampers to the maximum amount spoiled the riding of the 20HP. in respect to this particular point complaint, [but it is known that in other respects the riding is improved by stiffening up the shock dampers] Would it be possible to see by fitting the heaviest front springs available whether stiffening up the front springs still more has a similar adverse effect on the riding. DA.{Bernard Day - Chassis Design} | ||