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).
Modifications to valve and port sizes for testing and performance improvements.
| Identifier | ExFiles\Box 90a\4\ Scan226 | |
| Date | 20th May 1938 | |
| -3- Hs{Lord Ernest Hives - Chair}/Bwdl.11/JH. 20.5.38. We anticipate that by increasing the valve and corresponding port size that the reduced exhaust gas velocity will lower the seat temperature and also have an advantage in additional seat area. As the time for completion of the unit is getting short we should like to have ready 2 sets of No.276 valves and 2 sets of valves of similar shape of head to No.276 but 1.450 dia. We hope to have proved during the next day or so whether the larger valve gives any improved results with regard to pocketing. Attached is a curve showing lost clearance recorded on the bed against the hours of endurance running. Hs{Lord Ernest Hives - Chair}/L.H.Swindall. | ||