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).
Assessment of an American Bosch battery ignition system, comparing its governor, contact maker, and coil.
| Identifier | ExFiles\Box 37\1\ scan 223 | |
| Date | 16th February 1921 | |
| H.R. 555A (100 T) R.N. 798. 10-12-20: G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2947 X. 3949 Extract from Rll/G16.2.21. X.4275 - RE AMERICAN BOSCH BATTERY IGNITION. GOVERNOR. X.3949. We do not think the Governor is as efficient as the Delco pattern. It also gives a couple which can be easily detected by winding it round the hand. This may not do any harm, but it certainly exists, and one would expect that it had ill-effect on the bearings. CONTACT MAKER. X.1819. Regarding the contact maker and condenser, this appears to be a nice piece of work. Is this fitted with tungsten or platinum points ? There is no provision for preventing a back-fire when hand turning the engine, should the engine swing backwards. In this respect it is inferior to ours. When one comes to practical details, it would appear that there is great danger of the cam touching the arm in the event of the fibre being slightly worn away (the contact arm is the insulated part) much too near at this point. COIL. X.918. Regarding the coil, this seems a nice piece of work, though it is more bulky and expensive than our own. It has also the disadvantage that we should expect its efficiency is lower than ours, because the core is not of such a good form. Moreover, it is not so water-proof. We notice that the good looking mouldings of insulating materials add largely to the appearance of these units, but the brown material appears to be rather soft. We presume, however, that it is the best quality of bakerlite. | ||