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).
The decision to production test pistons made from R.R.50 alloy.
| Identifier | ExFiles\Box 15\3\ Scan047 | |
| Date | 3rd October 1930 | |
| To Sg.{Arthur F. Sidgreaves - MD} From Hs.{Lord Ernest Hives - Chair} c. to WCr. c. to By.{R.W. Bailey - Chief Engineer} X7040. Hs.{Lord Ernest Hives - Chair}3/MJ.3.10.30. X. 7040. X. 5040. Re. Pistons in R.R.50 Alloy. Replying to Sg{Arthur F. Sidgreaves - MD}32/E29.9.30. The position is that although a number of other manufacturers are using the R.R. Alloy exclusively for pistons we were not using it ourselves. There is no question of the strength of the material, the only point that we had to assure ourselves was whether it was necessary to modify the clearance of the pistons. In order to prove this it was thought that it would be a much better plan to make 20 sets of these pistons and let them go through a production test rather than rely on a single test on an experimental car. The advantages we expect to get from R.R.50 alloy is that pistons will retain their shape better and they should remain free from piston knocks for a longer period of time. It has never been laid down that a change in material demands a 10,000 miles test. Hs.{Lord Ernest Hives - Chair} | ||