Installation of Mega Spark 4 Coil

[xebec]

My 1971 Mk3 GT6 is fitted with Lumenition Optronic Ignition (fitted by PO) and 6 volt coil. The coil has seen better days and therefore I have decided to replace it with a MegaSpark 4 Coil but retaining the ballast resistor as previously installed. I am difficulties trying to figure out how to install it as it is wired as such:

The following wires come out of the loom:

Thick Brown wire to Alternator

Brown and Yellow wire to Alternator

White wire to top connection of ballast resistor

White/Yellow with Black wire from bottom connection of ballast resistor further connected to coil plus

Brown wire to red wire of the Lumention Optronic

Brown wire of the Optronic connected to negative connection of coil

 

I have attached a couple of photo's showing this setup as is. The problem is the only connection I am sure of regarding the Mega Spark Coil is the negative one to the brown wire of the Optronic.

The rest I am a little confused about especially when taking into account the instructions that came with the MegaSpark Coil as follows:

 

"Connection to a Vehicle with an existing Ballast Resistor.

Remove the existing coil. Connect the Positive (+) terminal of the coil to the ignition feed from the existing ballast resistor. An extra cold start wire may also be fitted here, coming from the starter solenoid. Connect the Negative (-) terminal to the Violet wire from the Optronic power module (may be a Brown wire on older units). The red wire from the Optronic power module can be connected to the ballast resistor on the ignition switch side. Reconnect the HT king lead to the top turret of the coil'' 

 

I am a bit worried about blowing up the Lumenition therefore I would be very grateful if someone could assist in the best way of installing the Coil.

Thanks & Regards, Ken

[Waynebaby]

Hi Ken,

 

The White/yellow wire with the black wire connected from the bottom of the resistor attaches to the positive side of the coil and as you say, you've figured out that the optronic brown wire attaches to the negative terminal. The white cold start wire referred to in the instructions is equivalent to the white/yellow wire on your car, so you don't need to worry about that and as your optronic power module already has a live feed you can ignore that part of the instructions too.

 

Just exchange the coils and put the two cables back on the new coil exactly as they are on the old coil and things should work. 

 

Hope that helps.

 

Wayne 

[xebec]

Hi Ken,

 

The White/yellow wire with the black wire connected from the bottom of the resistor attaches to the positive side of the coil and as you say, you've figured out that the optronic brown wire attaches to the negative terminal. The white cold start wire referred to in the instructions is equivalent to the white/yellow wire on your car, so you don't need to worry about that and as your optronic power module already has a live feed you can ignore that part of the instructions too.

 

Just exchange the coils and put the two cables back on the new coil exactly as they are on the old coil and things should work. 

 

Hope that helps.

 

Wayne 

 

That's brilliant Wayne, that's exactly what I needed to know. Thanks very much, appreciate your help. Regards, Ken

[Tiggers]

You probably already know this but for those that don't, to get the performance advantage of a high ouput coil you need to open the plug gap, and this can be 40 thou.