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).
Proposed design modification to the Phantom valve stem.
| Identifier | WestWitteringFiles\S\2April1928-June1928\ Scan056 | |
| Date | 26th April 1928 | |
| HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} C. to RI. BY.{R.W. Bailey - Chief Engineer} F.{Mr Friese} [strikethrough] R1/M26.4.28. ORIGINAL PHANTOM VALVES. X8060 X7060 [strikethrough] We find the Phantom valve to be thinner in the tulip than any other valve we are now using, irrespective of size, and I think there is very little doubt that it becomes entirely a question of design, and not material. We are sending you through a drawing - LeC. 2551. - shewing a modification to the head and stem. We are asking for the stem to be larger by an amount that we think can be got in on the present heads. The present stock of valves can all be marked 'inlet'. A difference in the stem diameter enables us to make the inlet valve stems a better fit than is obtained with interchangeable valves, and also avoids adding weight to the valve with the larger acceleration and reducing the maximum speed of the engine. R.{Sir Henry Royce} | ||