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 data comparing a new outside primary ignition coil against a Delco-Remy model.
| Identifier | ExFiles\Box 164\5\ img334 | |
| Date | 3rd March 1938 guessed | |
| NEW TYPE R.R. OUTSIDE PRIMARY IGNITION COIL. R.R. Delco. Primary Resistance ...... 2.865 W. 2.91 W. Secondary Resistance.... 3740 W. 4000 W. Primary Impedance....... 4.97 W. 3.55 W. Secondary Impedance..... 5700 W 5440 W. Primary Inductance...... .01292 henry .0065 henry. Secondary Inductance.... 13.7 " 11.72 " TESTED ON A 12 V BATTERY BENCH TEST. R.R. Delco-Remy. Sparks per Second. Kilo volt output. Primary current. Kilo volt output. Primary output. 20 15.2 2.30 11.3 2.40 50 15.1 1.98 11.9 2.17 100 14.0 1.40 11.4 1.85 150 12.4 1.22 10.9 1.62 200 10.7 1.00 10.2 1.60 240 9.5 .89 9.35 1.58 Slow running and low primary voltage test :- 25 R.P.M. R.R. Voltage. 4 6 8 10 Primary current 1.0 1.425 1.9 2.2 Kilo-volt output 4.9 7.0 8.9 10.0 Delco-Remy. Voltage. 4 6 8 10 Primary current 1.0 1.45 1.9 2.3 Kilo-volt output 4.7 6.6 8.4 9.6 Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||