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).
Tests conducted on new front springs and a roll-rod with various damper settings.
| Identifier | ExFiles\Box 101\2\ scan0117 | |
| Date | 16th October 1936 | |
| copy. GWH{George W. Hancock - Head Chateauroux}/IMW{Ivan M. Waller - Head of Chateauroux}/S/JAB HOTEL DE FRANCE, CHATEAUROUX, Indre. France. 16th October, 1936. To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. G.W.H. 22.G.V. Tests on New Front Springs & Roll-Rod. with various damper settings. The following combinations have been tried, the softening of the dampers in each case being affected by removing the bellows box and reducing the thickness of the washers behind the springs by .015". 1) Rear & Front Dampers, soft. 2) Rear Dampers standard, fronts soft. 3) Rear Dampers soft, front standard. 1) With all dampers soft, the roughness or bumpiness in the ride was practically eliminated, but the car tended to dive in front with a corresponding kick-up at the back and the net result was a ride that was no better than with the standard damper setting. 2) Increasing the rear damping to standard and leaving the front soft, did not overcome the pitching and made the rear ride rougher. 3) The arrangement was the reversed, the front dampers were put back to standard and the rear damper poundage reduced. This gave the best ride that we have been able to obtain and is a big improvement in all respects on the former suspension on this car except that there is a slight roughness in front since fitting the roll-rod, but we do not think it sufficiently prominent to be objected to, and it is not weighed by the other improvements. The rear seat ride is now practically free from the roughness previously experienced at low speeds on all kinds of bumps, and the general movement is less at higher speeds on bad roads. There is no undue throw up over bumps. The ride is not 100% comfortable, but is a big advance on our previous experience with this car. The car remains free from rolling with the reduced rear damper poundage and handles beautifully both on straight and winding roads. It is the roll-rod that has made possible the improvement both in comfort and control. | ||