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).
Suitability and modification of a crankshaft spring drive for a Phantom car's camshaft.
| Identifier | ExFiles\Box 65\4\ scan0259 | |
| Date | 14th August 1928 | |
| X8020 c HS{Lord Ernest Hives - Chair}/Mr Hancock. from Mx.{John H Maddocks - Chief Proving Officer} Hx11/T14.8.28. PHANTOM CAR - CRANKSHAFT SPRING DRIVE FOR CAMSHAFT. With reference to your memo BY10/G13.8.28 in which you confirm my recommendation to lower the poundage of the spring drive damping, I omitted to mention in my original memo on the subject that the 20HP Spring E53763 is not altogether suitable - it is satisfactory for poundage etc. but is rather difficult to erect when engines are fitted into chassis, as the external diameter of the spring is much less than the original spring. You are no doubt aware that the method of erecting this part is to use a small quantity of grease on the end of the 10 springs, just sufficient to hold them in the pocket whilst the part is being erected. On the experimental sets we have fitted, we have had to increase the diameter of the first coil of the springs to enable us to satisfactorily fit the parts together. I am sending you herewith a sample of both springs with the end coil increased in diameter at one end of the 20HP damping spring, also the 40/50HP Presser plate into which the springs fit. Mx{John H Maddocks - Chief Proving Officer} | ||