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).
Future chassis and engine design considerations, including rear axle, frame, suspension, and brake systems.
| Identifier | ExFiles\Box 148\5\ scan0095 | |
| Date | 19th November 1935 | |
| -4- The existing rear axle seems to us to be good for several years. It may require detail strengthening from time to time to cope with increasing engine output, but if the weight of the car is kept down, fundamental alteration will probably be avoided. The new frame might, we think, with advantage provide an opportunity for a simplified front suspension. The existing joint in the frame for the coiled spring pot has undesirable characteristics. We agree with Tsn. that the torsion rod scheme is worthy of examination again. The Buick scheme on a car selling for less than £200 in the States cannot be considered costly. The brake transmission will, we hope, be simplified. The servo will be as fitted to the Wraith box. It is improbable that SpectreCodename for Phantom III size brake drums can be used. It is therefore apparent that though in the programme so far economy of effort is indicated by the majority of the components being interchangeable between 20/25 and 40/50, apart from the engine and gearbox, the effort put into the Bentley applies to one chassis only. By the utilisation of the Peregrine engine a second car could be produced to make use of the Bentley chassis. This chassis would exactly resemble the Bentley in that it would only be expected to carry four people. We have always regretted that the Design and development work put into the Peregrine engine was discarded. If we had to design a small six-cylinder engine to-day, to give the maximum efficiency for a given sum of money, we should almost exactly reproduce the Peregrine with the possible exception of converting the cylinder head to a four port scheme. The unit may be considered rather small in view of the present requirements for performance. It can be increased 10% in displacement by using the present Bentley practice and probably 30% by deleting the water between the bores which make it a 3½ litre engine. It weighs about 1 cwt. less than the present Bentley unit and is more than 4" shorter. The ideal would eventually be that the small six would be half the large 12. | ||