On Sun, 5 Dec 2004 17:06:37 -0800, "Richard W."
wrote:


Most engines run with a 6 volt coil.The resistor is to bring the voltage
down from 12 volts to six volts. Fords use a resistor wire. Chryslers use a
ballast resistor. I don't recall what GM uses. When you start the engine the
system by passes the resistor so you are running 12 volts to the coil. This
is for cold weather starting. Once the engine is running the power is
rerouted through the resistor and you are then running the coil with the
proper 6 volts. Some cars use coils with the resistor built in.

Richard W.


Not true. Coils on 12 volt systems with resistors generally run on
closer to 8 volts.
6 volt coils are generally 1.14-1.26 ohms.
12 volt coils used wqith a resistor are generally 1.42-1.58 ohms. They
range from 1.25 to 1.73
12 volt coils for use without a resistor generally run 3.15 to 3.48
ohms, while electronic ignition coils, particularly CDI, generally run
well under 1 ohm, with 0.3 to 0.6 being common.