I am planning to install an electronic ignition in my 68 e-type S1.5. Does this e-type use a ballast resistor as part of the ignition system? Thanks.

 

Some do, some don't. What do the instructions say?

 

Instructions for the electronic ignition say use the ballast resistor if installed. If it has one, where would it be located on the car? Next to the coil?

 

Assuming no replacements were made, there is a resistor built into each molded clip connecting the lead to the spark plug.

 

The ballast resistor is a small ceramic resistor usually fastened close to the ignition coil.
Its purpose is to drop the voltage to 8-10 volts at the coil when the engine is running.
But when the engine is in START mode this resistor is bypassed by the key/ignition switch to deliver a full 12volts to the coil at start-up.
If all this sounds confusing it is because car manufactures noticed that there is a voltage drop when the starter is being used, so the coil doesn't get a full 12 volts during this start-up time ! Now this is to be understood as the factory setup on US series 2 E-types.
When we change to modern efficient starters and electronic ignitions we can dispense with
the coil ballast resistors and install a new 12volt coil ! It must be noted that high-tension ignition wires and spark plug caps are still necessary as these are required for RADIO SUPPRESION
INTERFERANCE and have nothing to do with coil resistors, these components are still used, unchanged with electronic ignition systems !

 

Here is a pic of the two ballast resistors on my 77 XJ6:

White Ceramic ballast resistor to the lower left of the Coil, and a shiny al-miny-um one to the lower right. I have posted a seperate thread and hope someone will tell me what the shiny alminyum one is for......Im restoring my 77 XJ6, and none of the shop manuals/parts manual/owners manual say what it is for. I have a Lumition electronic ignition added, and want to know if both ballasts are needed. Help.......