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).
Modifications and tests of the 4-wheel braking system on 20 HP cars.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan54 | |
| Date | 1st July 1925 | |
| R.R. 493a (50 H) (D.D. 31, 12-6-25) J.H.D. EXPERIMENTAL REPORT. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to RG.{Mr Rowledge} DA.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} E.{Mr Elliott - Chief Engineer} c. to WCr. Expl. No. ORIGINAL REF Hs{Lord Ernest Hives - Chair}6/LG23. 7. 25. c SECRET. Y.5770 Y.5940 20 HP. CAR FITTED WITH 4-WHEEL BRAKES. The 20 HP. cars which were sent to W.W. today were not fitted with the slotted rod between the servo and the rear equaliser because, so far, this scheme has only been instructed experimentally. We have, however, got this arrangement fitted up on another car. It does overcome the trouble it is intended to do, i.e., it reduces the load on the brake pedal for direct braking and it also enables us to increase the friction on the swinging arm so that we get rid of the tendency for the front brakes to thump. The 40/50 cars are all made with the pick up counter-shaft although there was a suggestion at one time that this was unnecessary. It has been arranged that all India production cars will have the slotted rod between the servo and the rear equaliser. We shall alter 9-G-11 car before it goes to France, and we shall alter 8-G-111 at the first opportunity. Dampers for eliminating brake squeaks. We have made a number of comparative tests to enable us to judge the relative efficiency of different types of brake dampers. The results shew that the present dampers fitted to 20 HP. cars are 50% efficient. The new dampers which are held contd :- | ||