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).
Secret memo discussing engine design and chassis development for the Wraith model.
| Identifier | ExFiles\Box 6\6\ 06-page034 | |
| Date | 14th October 1936 | |
| SECRET. To- Sr. and Sor. from E.{Mr Elliott - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} E.1/HP.14.10.36. re Wraith Chassis. Now that we have burned our boats and gone to the public with a new big chassis fitted with independent front wheel suspension, there is no doubt that the obvious conclusion will be drawn, more particularly with respect to the 20/25. It, therefore, becomes increasingly urgent to complete all necessary work in conjunction with the Wraith, and I am accordingly having a programme prepared with a view to fixing a date when the design work for the whole chassis will be completed. It will be remembered that the designs for a Straight '8' engine for this model were finished in January of this year, and instructions for the gearbox, and the major portion of the back axle were also issued at the same time. Before we are definitely committed to this type of engine I think we ought to seriously weigh up for the future whether we ought not to consider an alternative in the form of the Vee '8' in spite of the effect this might have on our programme. Some of the difficulties associated originally with this type of engine have somewhat disappeared, The induction pipe problem we believe has been solved, and the development of the downdraught carburetters has made things much easier. Bonnets of today tend to be wider and more capable of accommodating the width of this engine. The engine itself would be less wide with the shorter stroke and higher revs we should probably use. The balance of this engine is at least as good as the Straight '8', and it offers an opportunity on the lines of the SpectreCodename for Phantom III development of shortening space occupied by the power unit for the benefit of the coachwork, steering lock, etc. There is a little more difficulty in arranging room for a steering box perhaps if this is of the conventional type than on SpectreCodename for Phantom III, due to the position taken up by the cylinder blocks. | ||