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Just transfer the wires from the + terminal of the old coil to the + of the new one and the same for the wires on the - terminal.
 

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What year is your car? It looks like the earlier ignition system (81-83, I think). I have an '82 and installed an MSD coil, bypassing the ballast. It exploded after a few hours of running. I went back to the stock setup with a Bosch coil, which was about three times as expensive as the MSD, but have had no problems since. Based on additional reading I think the MSD is only compatible with the newer ignition system.
 

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Your mistake was to bypass the ballast resistors
 

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Gianni, measure the resistance between the screw terminals of the original coil and then the Blaster coil and report back.
 

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I run an MSD blaster in a couple of my cars (2002tii and Jensen-Healey) and the primary resistance of these coils is 0.7 ohms. I find these to be great coils for the money and last a long time if the overall resistance of the primary ignition circuit is within spec for the particular system.

The early GTV6 ignition system has an interesting double ballast resistor. I'll save myself some typing and copy and paste a post of mine from a few years ago:

"The early ignition system uses a double ballast resistor unit to limit primary ignition current, presumably to protect the circuitry of the ignition control unit. The solid green wire to the resistor is connected to terminal 16 (an old German DIN designation for the resistor bypass circuit) of the ignition switch, which is only active while the starter is cranking; this is to provide the ignition primary circuit with more current while cranking to ensure adequate secondary voltage for cold-starting the engine.

When the starter is engaged, current flows from terminal 16 of the ignition switch and to the upper connector of the resistor unit, and it travels through only one of the 0.6 ohm resistors and on to the coil positive terminal. When the ignition is switched to terminal 15/engine running, current flows from terminal 15 of the ignition switch to the ignition control unit, but it is forced to travel through both resistors (for a total of 1.2 ohms resistance) before reaching the positive terminal of the coil. This limits the overall current of the primary circuit while the key is on, engine running or not.

In older cars, a ballast resistor was used to prolong the life of the ignition contact points, and the circuits that I am used to (older BMWs, for example) use a relay that is activated by terminal 50 of the starter to bypass a single resistor while the starter is cranking."
 

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Discussion Starter #7
@alfaparticle i am reading 1.3 on my old one and 0.80 on the MSD . Ideally I would like to get rid of the resistor but when I transfer everything on my MSD and bypass the resistor I’m not getting spark. I have a wire going from my ignition going straight to my + and then I have a wire going from my - to my silver ignition box and another one going to my ECU
 

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The MSD coil might be too low resistance to use in that circuit without another ballast resistor. If the MSD came with a ballast resistor of about 0.7 ohms then you should connect it in series with the + terminal of the coil. You risk blowing the trigger module if you run with low resistance coil without additional resistance.
In your original post you did not state model rear and I wrongly assumed that you had the more common ignition without ballast resistors.
 

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Discussion Starter #9
@alfaparticle and is it normal that my resistor gets very hot ? Ps:my car doesn’t have the original fuse box anymore as it’s a race car. Should my resistor be connected strait to my ignition so always hot?
 

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It might get hot if you left the ignition switched on when the engine is not running.
I am not an expert on the early GTV6 circuits, I only know the later ones so someone else will have to help you with that.
 

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Hi Gianni,

Why are you replacing the ignition coil? Is the original Bosch unit faulty?

You should get your hands on a wiring diagram to be 100% sure of which wire is which, but my post above does describe to the resistor should be wired. Terminal 16/resistor bypass (green wire from ignition switch) should go to the top terminal of the resistor, Terminal 15 (switched ignition) should go to the bottom terminal towards the rear of the car, and the wire to the ignition control unit/amplifier should connect the to bottom resistor terminal towards the front of the car.

If you are not getting spark while cranking, it is possible that you have this all wired incorrectly.
 
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