41 Ford Starting Problem

[joes41]

My 41 Woodie often will not start unless I bypass the resister by running a wire from the battery to the connection on top of the coil. When I do this it fires right up and I pull the wire off. I have an 8 volt battery and the voltage regulator has been adjusted so the battery charges. The problem exists when the engine (V8) is cold or hot. I would appreciate any suggestions. Thanks, Joe