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).
Comparison of specifications for distributors and ignition coils.
| Identifier | ExFiles\Box 164\5\ img112 | |
| Date | 3rd December 1931 guessed | |
| DISTRIBUTOR COMPARISON DF6 Rolls Royce Distrib. Diam. of jump spark track 2" 2.27" Tracking distance between} 1.5" Inside 0.9" outer segments } distrib. Tracking distance between} 1.6" 1.125" centre and outer segment.} Material of Segments. Brass Nickel Diam. of segments. 0.375" 0.16" Tracking distance between} 2" Outside 1.5" outer segments. } distrib. Tracking distance between} 1.9" 1.6" centre and outer segment.} Length of Heel. 11 mm. 8.5 mm Material of Heel. Bakelised cloth Fibre. Bearing - Lubrication. Graphite filled Ball bearing (withoiler) with oiler. Cam lubrication. None None Cam closed period. 40.5° 33° " open " 19.5° 27° Gap at contacts. 0.15" .18" - .020" Spring pressure on heel 32 ozs. 24.4 ozs. COIL COMPARISON OQ68 Rolls Royce Ballast resist cold 1.4 1.64 w " " hot 4.88 Primary resist cold 1.0 .89 " " hot 1.0 Hot starting factor (calculated)60% 73% with .12 mfd 100% " .54 " contd. | ||