I wonder why GM changed to a "12v" coil in 1955 12v cars, but stayed with a "6v" coil in early 1955 6v trucks? "Hotter/higher" starting voltage - easier starting?
I always thought the ballast resistor decreased the voltage to around 9v?
The 1955-2nd Shop Manual does say the operating (not starting) voltage at the coil should be no higher than 7v (12v electrical system).
