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).
Engine testing procedures for B.80 No.1 and No.4 units, including camshaft and crankshaft modifications.
| Identifier | ExFiles\Box 155\2\ scan0332 | |
| Date | 30th June 1939 | |
| -2- B.80 No.1 - Cont'd.{John DeLooze - Company Secretary} Starting with .010, if even, further reduce tappet clearance until idling is on verge of being uneven. If uneven increase tappet clearance until even running is obtained. In this way it will be possible to compare the merits of the camshafts on the tappet settings. A value should also be obtained on each shaft regarding the maximum tappet clearance for quiet operation, also the valve bounce speed. When the tests on the existing EB.4105 shaft have been completed, remove the unit and we will instruct for the next shaft to be fitted. In the meantime, B.80 No.4 will be ready and should be fitted on bed. B.80 No.4 UNIT. Unit as before (see Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}8/JH.25.5.39), but fitted with the following new parts. (i) Crankshaft with spring driven crank pinion and harmonic damper, ECD.1246. (2) Ex. camshaft After running in for new parts take - (a) Open exhaust power curve on existing timing, also ½ tooth late and ½ tooth early. (b) On best timing run curve with exhaust system as used for camshaft tests and on Redline check non detonating line and ensure that governor has right characteristic. (c) Obtain value for idling. (d) Spooner to take crank and camshaft oscillations. (e) Run 10 hour endurance under conditions of previous endurance on B.80 No.3, but with fan. (f) Finally tune up in readiness for chassis. | ||