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).
Comparing the weights and braking performance of two 40/50 HP cars and a Hispano Suiza.
| Identifier | ExFiles\Box 3\2\ 02-page100 | |
| Date | 13th November 1923 | |
| X 200 X4214 /X200 /X226 To DA.{Bernard Day - Chassis Design} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}/L.13.11.23. In reply to your Da{Bernard Day - Chassis Design}1/M13.11.23., the following are the weights of two representative 40/50 HP. cars and the Hispano Suiza - all without passengers. 6-EX Car - open touring. Wt. front - 2128 lbs. Wt. rear - 2408 lbs. 4-EX Car - Saloon. Wt. front - 2334 lbs. Wt. rear - 2772 lbs. Hispano Suiza. Wt. front - 2324 lbs. Wt. rear - 2576 lbs. It will be observed that on the two 40/50 cars, the ratio of the weight over the back axle to the total weight, varies but little with different types. hence, neglecting the shifting of the weight due to deceleration, the two cars should be able to pull up in practically the same distance if the wheels are locked in each case. As regards pedal leverage. As the weight over the rear axle of 4.EX car is more than that on 6.EX Car, one would say that more pedal pressure would be required to bring the former to rest. In practice we frequently get the reverse results as the bedding of the shoes and other adjustments are capable of making an enormous difference in the pedal pressure required to produce a given braking affect. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||