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).
Requirements for fitting a new flywheel and clutch to the J.III model.
| Identifier | ExFiles\Box 103\1\ scan0026 | |
| Date | 19th April 1933 | |
| x 5300. By.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}14/KT.19.4.33. FLYWHEEL & CLUTCH. J.III. Re. DA{Bernard Day - Chassis Design}1/M5.4.33. We should like to fit to J.III the type of clutch we are now using on Peregrine. This can be done either by scaling up N.sch.3654 or modifying N.sch.3654 to suit the J.III crankshaft. We think we could work with a theoretical movement of the pressure plate of .080, the inner sprung plate to have .010 movement giving an effective calculated separation of .070 Further we should like LeC.3418 clutch spring drive modified to suit. At the same time it is an opportunity to arrange for both the flywheel ball race and clutch splines to suit the 20/25 1st. motion shaft. We should be glad if you would detail a clutch in accordance with the above to transmit 208 lbs.ft. torque at a Pa{Mr Paterson} of .180 The friction surfaces should be Millinite and Ferodo RAD.13. We attach a scheme of needle roller bearing operation that we have fitted to the 40/50 clutch. We should like this incorporated also. The pedal effort is always going to be high on this car since we are using a 20/25 size clutch on a 4½ litre engine. Again, we should like to start the clutch pedal level with the brake pedal, slotting the floorboards to allow for wear. We consider .012 allowance sufficient. We cannot send 1.J.III car to France until we have the new clutch. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||