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).
Testing methods, spring ratings, and passenger weight distribution calculations for car suspension.
| Identifier | ExFiles\Box 72\2\ scan0042 | |
| Date | 28th August 1926 | |
| - 3 - was done in the opposite direction and the mean taken, and it was astonishing the consistency of the results obtained; the effect also could be noted of alterations in tyre pressures and shock absorber settings. I realise this method is perhaps too crude to appeal to you, but it was the only way I had of tackling the job with my limited apparatus. By the way, I am rather puzzled by the rating given of the springs you required for 82LC, London Trials Car and 8EX which is approximately 480 lbs. per inch; a very different figure for rating to that given in your reports on suspension under heading of "Fundamentals of Car Performance" Hs{Lord Ernest Hives - Chair}/RmL/LG-28-8-26, page 24, which show a rear cantilever spring rating of only 125 lbs. per inch of deflection. Pt. M.{Mr Moon / Mr Moore} P.S. By the way, in the last two paragraphs on page 1 of this letter I neglected to make it clear that the word "passengers" means, in the case of the front axle half the maximum front seat passengers and in the case of the rear axle half the maximum front seat passengers plus half the maximum rear seat passengers. In the case of seven seater bodies, I calculated upon three rear passengers and one front passenger, in arriving at rear axle weight. 6 / 2000 / 333 18 / 200 | ||