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).
Conclusions from tests on engine backfiring related to ignition and throttle settings.
| Identifier | ExFiles\Box 107\1\ scan0435 | |
| Date | 22th January 1937 guessed | |
| 5. Conclusions. During these tests the writer has tried numerous standard test cars, and has found that although they vary slightly in the amount of throttle opening necessary, the results obtained with G.b.G. 5 are parallel on all production cars. We have found that no engine backfires if the ignition is switched off with the engine throttled back to tick over position, and that it only occurs if the ignition is switched off immediately after running the engine hard, and the throttle is set for the engine to run fairly fast. We have realised from all the tests we have made how small the margin of safety is, and we shall proceed further on our experimental engines to try and improve on this. Rm{William Robotham - Chief Engineer} / f.{Mr Friese} Avard. | ||