Specification changes for front springs, carburettors, ignition, petrol supply, and gearing.
| Identifier | ExFiles\Box 5a\1\ 01-page177 | |
| Date | 1st July 1931 | |
| -2- R2/MB.7.31. contd. FRONT SPRINGS. We have decided to lengthen the front springs by 2" although they are already longer than on other chassis of similar size. CARBURETTERS. In the specification of the engine we need not decide at the moment whether we use one or two carburettors. It will depend upon Derby's experience with the test carburettors we can design and those that can be bought. At the moment we believe it will be 2 separate single fixed jet non-expanding carburetters, the designs of which have already been sent to Derby. IGNITION. Regarding ignition it is decided that we abandon fitting the magneto and have a single battery ignition, much the same as present 'China(Experimental Engine)'. We shall however, arrange that in the spares carried on the car there will be a coil, a contact maker, and a condenser, so that any failure of this ignition need not delay the car, where-ever it is, more than a few hours, providing that the supply of current is available. PETROL SUPPLY. This will be by pump instead of autovac. CHANGE GEAR. This has already been designed to have single helical constant mesh gears for the 3rd, with synchronous mesh change, for which we are expecting to have to pay a royalty to General Motors. We believe that Derby and W.W. are in complete agreement with this specification and we do not think that at the moment there is any necessity for a conference unless some-one reading a copy of this memo objects to any detail, or is discontented with this specification. (Regarding the present 'China(Experimental Engine)' we do not propose to alter this more than is at present in hand, that is, getting the best we can out of the engine as it stands and improving its appearance with the deeper radiator. We conclude that it will be necessary to get going with this until J.2. is ready. The exact date of this cannot at present be decided, we never know in the designs what difficulties we shall meet and what changes will be necessary. For instance, tomorrow we might learn how to build a distinctly better engine of quite a better type. We believe however, that we have adopted in the designs in hand all the knowledge we have at present, and that no serious changes will be necessary). P.S. Advance copy - hope to complete this tomorrow with print of chassis as intended. The 16 HP. is 8/10ths. linear scale of this Japan(Experimental Engine) 2. | ||
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).