I realize the cables to the solenoid and starter should be 0 or 1 gauge for 6-volt systems however is it necessary to run this gauge for the ground cable? Would a 12-volt thickness be good enough for the ground? Thanks. Steve
6 volt needs the bigger cables 12 volt can use the 6 volt as the current is half the amount. larger the needed cables no problem smaller than needed big problem.
I am using the heavy cables for both positive & negative for both my 55 F-100 and 46 Coupe. However, the stock braided grounding strap used on the Model As and early V8s seemed to do well and were not thick as the cables many of us use now for our 6-volt systems.
I use a 12 volt cable for a ground after I run initially to the frame with a ground strap but I also have several ground cables. The cable from the battery to the frame needs to be heavy.