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).
Weight analysis of the Wraith II chassis and strategies to prevent it from becoming heavier.
| Identifier | ExFiles\Box 10\5\ 05-page007 | |
| Date | 2nd May 1928 | |
| Handwritten: Les.{Ivan A. Leslie} Should like to have your comments Kim Sg.{Arthur F. Sidgreaves - MD} and Wor.{Arthur Wormald - General Works Manager} from E.{Mr Elliott - Chief Engineer} c. Lln. Ev.{Ivan Evernden - coachwork} RHG. Ds. HV. Edy. and C. 658 re Wraith II Chassis. With reference to the question of the weight of Wraith II chassis, we are going to strongly oppose any question that this is, or need be, any heavier than the present 25/30. We have been over our figures carefully again, and I attach herewith a sheet (No.2) showing the analysis, from which it will be seen that our present estimate for frame weight shows an increase of 4.5 lbs only, using the lightest gauges of material we think permissible. Sheet 1, attached, shows our estimate for the front suspension which is lighter than the experimental department estimate, based on using lighter linkages, levers, front cross member and frame complete etc. than Phantom III, and shows an increase of 86.5 lbs over the 25/30. On the other hand there are certain savings in our Wraith specification, shown on sheet 2, which are definitely in favour of preventing the Wraith chassis being heavier than 20/25. The nett result is that the Wraith II chassis comes out 9 lbs heavier than 25/30. Another point that we must not forget is that by the time the Wraith chassis comes into production, custom built steel coachwork may be available, and on this we expect definitely to make a weight saving of 50 lbs per body. My view is, therefore, that the Wraith II is not going to make a heavier motor car than our present 25/30, and I am strongly hopeful that there may eventually be an appreciable difference on the right side. It is important that we should keep this car from continually growing until it gets as large as the Phantom, since it fills a very important class for which there is an extensive demand at the present time, and we appreciate that Sales are prepared to restrict their demands for increased body space if necessary, to accomplish this object, but we hope that further restriction will not be necessary. ATT. E.{Mr Elliott - Chief Engineer} | ||