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).
Test report on a Goshawk ignition coil, comparing its performance under various conditions and gap settings.
| Identifier | ExFiles\Box 45\4\ Scan131 | |
| Date | 9th January 1923 | |
| X.4079 9.1.23. X.4079 - GOSHAWK IGNITION COIL Car 3G.II . K.L.G. plugs set at .030" Low tension make and break set at .010". All conditions the same as on previous coil tests. Coil having larger core than previous coils. With a gap above .025" coil misses fire slightly at low speeds and picking up with retarded spark. This compares favourably with Mr. Brock's No.III coil but is no better. With an outside gap of .040" this coil fails completely under ordinary running conditions (water temp. at about 75°C). This is not so good as Mr. Brock's No.III, which has never been made to fail completely, and will fire perfectly at high speeds with a gap exceeding .125". (sgd) A.J. Lidsey. | ||