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 scheme for the Silver Ripple crankshaft and cylinder head.
| Identifier | ExFiles\Box 118\1\ scan0376 | |
| Date | 4th January 1944 | |
| CONFIDENTIAL 1022 To. Wym.{G. Harold Whyman - Experimental Manager} from Jnr.{Charles L. Jenner} c.c. to. Rm.{William Robotham - Chief Engineer} Ev.{Ivan Evernden - coachwork} Ev{Ivan Evernden - coachwork}/JD.{J. Draper - Frames} Ev{Ivan Evernden - coachwork}/AH. Silver Ripple. PL.2869. Crankshaft & Cylinder Head. Reason for scheme: With the increase of the size of the engine from 2.950 to 3.250 it follows that the crankpins of the crankshaft should likewise be made bigger. Making the pins 2" dia. permits us to rationalize the Conn Rods. The rods can be passed through the cylinder bores when assembling the engine. This does not affect the crankcase or any part of the engine, other than the piston; these should be full length and flush with the top of the block. Description of the scheme: The pins are bared out as also are the journals for lightening and the shaft is machined and profiled all over, undoubtedly this will be the shaft for the first few engines. The pulley for auxiliary drive at the front is now a push fit on the shaft in place of a taper, the nut holds on both the pulley and the timing gear. Ev{Ivan Evernden - coachwork}/Tln has promised to design the flywheel disc and bearing housing for the 1st motion shaft. Instructions: Em/HH please to detail and Wym{G. Harold Whyman - Experimental Manager} to decide how many shafts are required for testing. General Notes: We thought it as well to shew the cylinder head on the same drawing, it is to PL.525 and is of the "ORIGINAL" type, being less rough than the "intermediate", the latter however is the one now running on the 14 HP. 6.5 to 1 comp. ratio has been selected, this is about as high as we dare go to on a 4 cylinder engine mounting under torque reaction. The crankshaft could be produced with black edges to the slabs and balance weights when a forging from a die can be made, this is shewn on PL.2869. Jnr.{Charles L. Jenner} Prints: Wym.{G. Harold Whyman - Experimental Manager} Ev{Ivan Evernden - coachwork}/JD.{J. Draper - Frames} Ev{Ivan Evernden - coachwork}/HH. Ashby. | ||