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).
Performance tests on a Graham Supercharger and requesting an order for worms with specific speed ratios.
| Identifier | ExFiles\Box 126\1\ scan0134 | |
| Date | 5th July 1934 | |
| To RHC.{R. H. Coverley - Production Engineer} x209 Hs{Lord Ernest Hives - Chair}/Smth.5/KW.5.7.34. Graham Supercharger. We have now completed the performance tests on the Graham blower and estimate we shall require an overall speed ratio of 5.5/1 when it is attached to the Bentley to give the same boost pressure as on the Graham. Will you therefore order a pair of worms giving a ratio of 3.67/1, in addition to the pair of 4.34 ratio as instructed in our Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}10/KW.15.6.34. Hs{Lord Ernest Hives - Chair}/Smth. | ||