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 results for nine E.W.6 magnetos, detailing safety gap, tangential force, and lowest sparking speed.
| Identifier | ExFiles\Box 65\3\ scan0189 | |
| Date | 8th February 1928 | |
| X9791 EFC. SFT{Mr Swift}/JMW10/DB{Donald Bastow - Suspensions}8.2.28. In reply to your memo EFC7/T.6.2.28., we have tested 9 - E.W.6. Magnetos with the following results. Mag. No. Length of Safety Gap. Tangential Force. Lowest sparking speed. fully retarded. 105321 8.2 m.m. 2 lbs. 200 R.P.M. 105320 8.3 m.m. 2 lbs. 210 " 105317 8.2 m.m. 1 1/2 lbs. 230 " 105319 8.2 m.m. 1 1/2 lbs. 190 " 100100 8.2 m.m. 2 1/2 lbs. 200 " 105304 8.1 m.m. 2 lbs. 220 " 100099 8.3 m.m. 1 3/4 lbs. 190 " 105303 8.2 m.m. 3 lbs. 210 " 105301 8.1 m.m. 1 1/2 lbs. 200 " SFT{Mr Swift}/JMW. | ||