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).
Second report from the Design Committee detailing modifications for the 25 HP model.
| Identifier | ExFiles\Box 12\5\ 05-page186 | |
| Date | 7th February 1930 | |
| R.{Sir Henry Royce}(Held up). Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair} x7360 Rg.{Mr Rowledge}1/LW.7.2.30. X.2924 X.5770 X.5005 X.5840 X.7360 SECOND REPORT OF DESIGN COMMITTEE. 25 H.P. MODIFICATIONS. The rubber mounting rear engine feet design was reviewed and the experience with this engine foot was gone over. It is recommended that this scheme should be adopted and fitted to the car going for 10,000 miles test, subject to certain very small modifications which are:- slightly harder rubbers, and the addition of a steel cup to make the job safer in the event of a complete failure of a rubber. It was decided that the 10,000 miles test car should have the 11/50 ratio axle. It is assumed that testing on the car with this ratio will standardise both the 11/50 and the 12/50, and that either of these ratios could be offered to customers. The 11/50 is the more severe test. The compression ratio of the engine for 10,000 miles chassis will be increased from 4.8 to 5¼, with modified ignition timing as reported on by Hs{Lord Ernest Hives - Chair}/AJL2/MJ6.2.30. We recommend that the actual axle to be fitted to the 10,000 miles car should be a hypoid axle which is in existence, and we consider we have had plenty of tests with the present axle. This does not mean the hypoid axle will be instructed for production at the same time as the other modifications. It is desired to run this car with lubricated spring leaves. The details already exist, and Hs.{Lord Ernest Hives - Chair} states that having the hypoid axle and the lubricated spring leaves will not cause any delay in the commencement of the test. The modification to the carburetter, boring out the chokes to increased size will be on the 10,000 miles car and on the production chassis. The exhaust pipes as made up and fitted on an Experimental car were examined and are recommended for production. Further tests are in hand to make sure whether a steadying stay is necessary. We are fitting on the 10,000 miles car a larger output dynamo which is in existence. This will not be instructed for production until after the test. | ||