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).
Design and material of exhaust valves for the P.2 model following a 10,000-mile test.
| Identifier | ExFiles\Box 14\6\ Scan205 | |
| Date | 13th August 1931 | |
| HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} X7230 R1/M13.8.31. C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} P.2. IN FRANCE. 10,000 MILES TEST. EXHAUST VALVES. --- There seems no explanation of why the new exhaust valves were any better than those which lost clearance. Are these of the same material and design. We consider they should be improved if no explanation can be given but the possibility of defective materials. Our later designs are less tulip-like and thicker in the head, bigger dia. of stem. Over 3 yrs. ago we asked for a .480 stem instead of .432 which E.{Mr Elliott - Chief Engineer} says is Silver Ghost dia., so these valves are out-of-date entirely - see 'China', LeC. 2780. Originally P. 1. had too much light and tulip-like valves, and these seem to have been improved at the end of 1928, (eight months after we asked for a bigger stem,) but still no bigger stem. Even this now being 3 yrs. old is quite out-of-date considering the increased HP. of P. 2. at present, and proposed. R.{Sir Henry Royce} | ||