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).
Secret memo discussing the introduction of an overdrive gearbox on the Continental Phantom III model to prevent engine failures.
| Identifier | ExFiles\Box 92\6\ scan0175 | |
| Date | 2nd July 1937 | |
| SECRET. Sg.{Arthur F. Sidgreaves - MD} from Rm.{William Robotham - Chief Engineer} Hs.{Lord Ernest Hives - Chair} c. to By.{R.W. Bailey - Chief Engineer} RHC.{R. H. Coverley - Production Engineer} Rm{William Robotham - Chief Engineer}6/R.2.7.37. CONTINENTAL P.III. Now that we have got the overdrive gearbox to a point where we think that it will satisfactorily complete its endurance tests, we are particularly anxious to reap the benefit of the reduced engine speed as soon as possible on P.III cars we are producing which are likely to be driven hard. The recent epidemic of big end failures on the Bentley is only a warning of what is bound to happen on the P.III when driven hard with the present axle ratio. It occurred to us that if we were modest with the specification, we could use the Continental P.III as a means of getting the overdrive box into the hands of these hard drivers quickly, and at the same time, use up the material for the standard box which is in existence. If something like this is not done, judging from other parts, it may be 12 months - RHC{R. H. Coverley - Production Engineer}5/MJ.5.7.37 - before we shall have an overdrive box. We attach a list of parts which are at present fitted to the Continental P.III, and which we think would satisfactorily go through 15,000 miles' test. Some of them suggest they might be more trouble than they are worth on production; others, which we have marked with an asterisk would be directly applicable to the Second Series P.III. If the general policy is agreed by Sales, it would be necessary to go through the proposed specification with production to see how the altered parts fit in with their programme. We should recommend selling this Continental P.III with hydraulic tappets deleted, as on 32-EX, to get a value for these in the hands of a few customers before committing ourselves to it for full production. The saving in cost is, of course, appreciable. 32-EX will, in the next few weeks give us a figure of merit. In building this car we consider it should be agreed that no extra performance should be got out of the engine unless this could be obtained without increasing | ||