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).
Research into frame stiffness requirements, comparing the performance of Cadillac, Spectre, and Bentley frames.
| Identifier | ExFiles\Box 94\4\ scan0064 | |
| Date | 2nd November 1935 | |
| X327 To E.{Mr Elliott - Chief Engineer} c. to WOr.{Arthur Wormald - General Works Manager} c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}5/KW.2.11.35. Frame Stiffness. We have had a letter from Cy., in which he says that after considerable research they have found the stiffness of the front and rear ends of a car required for freedom of jellying and longevity of bodies. In particular for the latter consideration he says the overall stiffness between wheel planes must be 3000 lbs.ft. per degree to prevent cracking up of the body. The Cadillac frame does not come up to his requirements for a "soft top" body; the complete car after testing in France, however, is just within his limit. The results he sends us are of course much later than the design of the V-16 Cadillac, and are backed up by figures for other American cars free from jellying. The attached list shows how our cars differ from the ideal; in particular the rear end of the SpectreCodename for Phantom III frame, which is about one third the suggested amount. Although the SpectreCodename for Phantom III frame is a vast improvement over the Phantom II, we do not think it will be adequate for a "soft top" or drop-head body. The Bentley frame and complete car are exceedingly weak and greatly in need of improvement. We think Cy's figures should be taken into account when designing a new frame, and that models should be tested before the Complete Cars are made. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||