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).
Comparative testing of cast iron versus aluminium pistons in specific trial cars.
| Identifier | ExFiles\Box 35\2\ scan 192 | |
| Date | 17th January 1920 | |
| R.R. 235A (100 T's) (S.F 816 6.8.19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460 Contd. -2- Hsl/LE/17.1.20. should be to get several sets of cast iron pistons as soon as possible. We should fit sets of these pistons to the London Trials Car and Mr. Hanbury Cars. They have now run for a fair time on aluminium pistons and if we change them to cast iron they should be able to notice the difference in the Cars, when fitted with cast iron pistons. I feel that the only difference they will find would be a slight increase in detonation. I am sure, from our last talk with Mr. Royce, that he is quite prepared to change over to cast iron pistons until such time as we have absolutely proved that we have succeeded in making an aluminium piston which remains silent. MADE AT CROXLEY Hs.{Lord Ernest Hives - Chair} | ||