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).
US automotive components including clutches, camshafts, and supercharging.
| Identifier | ExFiles\Box 178\2\ img208 | |
| Date | 23th February 1934 | |
| COPY OF REPORT RECEIVED FROM Rn.{Mr Robinson} IN U.S.A. DATED 13.2.34. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}5/KW.23.2.34. To Mr. [illegible] Mr. [illegible] Mr. [illegible] Mr. [illegible] c. to EV.{Ivan Evernden - coachwork} LONG CLUTCH. I send you a drawing of the single plate long clutch as fitted to the Lincoln and Pacard. The Lincoln dimensions are slightly smaller and are given in pencil. The over-all ratio as used on the Pacard is 61.38. They get the .060 separation with about 4.25 clutch pedal travel .65 being spring. They fit needle bearings in their cross-shafts. With clutch springs of 1850 they have only a pedal pressure of 30 lbs. they allege, which seems improbable as it is 100% efficiency. If you can make use of this clutch on the SpectreCodename for Phantom III or would like one to refer to, will purchase on receipt of cable. Clutch driven member weighs 7.5 lbs. Cover plate assembly 35 " Max. torque for which designed 325 lbs.ft. Max. out of truth running of centre plate .015. CAMSHAFTS. I noticed that Hudson Essex used a very lopsided camshaft, as we have frequently done in the past. If we get one of the new cars it will be worth studying as it must be efficient. Generally speaking, I have not seen a camshaft to give good slow running that has more than 1° or 2° overlap measured at .020 tappet clearance. SUPERCHARGING. G.M. seem interested in the Graham Supercharging. They say it gives them M.E.P. where they can use it. They already find they can get 110 M.E.P. at 1000 R.P.M. which is all they can use because of detonation, hence they do not want boost low down (this reasoning is not correct I know but probably, when coupled with the torque reaction difficulty, approx. so). | ||