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).
Test report page detailing performance results after cleaning a cylinder and testing a different valve spring.
| Identifier | ExFiles\Box 105\3\ scan0284 | |
| Date | 12th September 1932 guessed | |
| -5- when another diagram was taken this was not confirmed. However, when the cylinder was again removed, cleaned in petrol, dried, and another diagram immediately run off at this speed, the first diagram was confirmed. The same performance repeated at 180 r.p.m. did not produce such good results. A valve spring having a rating of 100 lb/in - half that of a standard spring - did not prove to be of much advantage, and the diagrams showed the same peculiarities (a and b) as were observed with the standard rating spring. 3 prints att. | ||