The voltage is a simple matter to figure out.

The voltage is dependent on the resistance of the coil and the ballast. If the ballast resistance is 1.2 ohms and the coil resistance is also 1.2 ohms then they will both drop half the voltage. So if the voltage at the input of the ballast is 14v, then you will see 7v at the coil + terminal.

If the ballast is 1.2 ohms and the coil is .6 ohms with input voltage at 14V you will see 4.7V at the coil with the rest being dropped by the ballast resistor.

http://www.allaboutcircuits.com/vol_1/chpt_5/2.html

What other people see is not germane to your setup unless they are using the same ballast, same coil and have the same input voltage.

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.