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).
Letter to Dr. J.C. Morrison providing engine specifications for standard Bentley and O.H.C. Bentley models.
| Identifier | ExFiles\Box 134\1\ scan0013 | |
| Date | 16th August 1937 | |
| 1129 Rm{William Robotham - Chief Engineer}/Ed.{J. L. Edwards}7/AP. August 16th 1937 Dr. J.C.Morrison, The University, GLASGOW. Dear Dr. Morrison, Many thanks for your letter. I must apologise for not answering before. I spoke to Mr.Robotham on the subject of your 'overtime', and he suggests that you do not bother about the Phantom III, but rather concentrate on the Bentley. I am therefore enclosing the stuff you asked for on the Bentley, but have not bothered about Phantom III, partly because the back pressures you want on this latter would have to be run off an engine which would necessarily mean some delay. The figures required are as under:- BENTLEY Ratio of conn. rod to crank = 3.54 Compression ratio = 6.3 Inlet valve lift @ T.D.C. = .026" @ 10° A.T.D.C. = .068" @ 20° " = .123" @ 30° " = .178" @ normal tappet clearance (.004") O.H.C. BENTLEY Ratio of conn. rod to crank. = 3.54 Compression ratio. = 6.3 Inlet valve lift @ T.D.C. = .035" @ 10° A.T.D.C. = .092" @ 20° " = .153" @ 30° " = .216" @ normal tappet clearance (.004") Ratio of inlet valve area Standard Bentley = 2.02 O.H.C. unit = 2.87 In the above I notice that you have asked for inlet valve data. I hope this is O.K. continued | ||