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TFI upgrade..2 ignition modules...failed

TFI upgrade..2 ignition modules...failed

83power

Jeeper
Posts
61
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11
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0
Location
Sudbury, Ontario
Vehicle(s)
1983 CJ-7
258 Inline 6, 4.2L
Automatic
Hello,

I have completed the Team Rush upgrade in my old 83 CJ7 , I-6.

I do not have a Ballast resistor.

First ICM was the original, so I thought it was just old and failed.
The second one was brand new and it has failed as well.

Both got hot and then failed.

I realize the upgrade increases the power in the entire system, but there must be something else I can do???

Is the BALLAST RESISTOR a must ???
 
Rather than a ballast resistor there is a resistance wire coming from the #1 post on the alternator to the coil, which is a small dia. brown wire, this cuts the voltage down to 6 volts to that coil. I have shortened my wire to send 9 volts with no issues. From what I have heard even 12 volts to the oem Motorcraft icm will not hurt it. It is possible your icms are dying due to a poor ground, this is the black wire from the icm to the distributor which is a poor way to do it. The best way to ground the icm is to run that black wire direct to the battery negative. There could also be a problem with the wire from the negative battery terminal to the engine block. Another possibility is the quality of that icm, a good one is the Echlin brand made by N.A.P.A., rather than to buy one made in China. An MSD ignition is another alternative.
 
Google "Stealth HEI". The GM modules hold up a lot better than the duraspark, especially given that the duraspark modules that are available now are chinese :dung: (unless you buy a used OEM module).

I put an HEI module on my tan Jeep in 1995 and haven't had any trouble out of it at all since.
 
Hello,

I have completed the Team Rush upgrade in my old 83 CJ7 , I-6.

I do not have a Ballast resistor.

First ICM was the original, so I thought it was just old and failed.
The second one was brand new and it has failed as well.

Both got hot and then failed.

I realize the upgrade increases the power in the entire system, but there must be something else I can do???

Is the BALLAST RESISTOR a must ???

OK, some 'Clarification' here...

There isn't a 'TFI' upgrade that I know about.
No one is using the Ford TFI module mounted on the side of the Ford distributor.

We DO use the E-core coil from the TFI ignition sometimes, especially when you switch to an HEI style module...
Sometimes called the 'John Strenk Steath HEI Swap'...

-------------------

Now,
*IF*...
You swapped to an E-core ignition coil (Ford or GM style external coil),
That particular coil has LESS RESISTANCE than the factory Canister Coil.

That INCREASES the current the module has to handle, and often causes the old factory, or almost worthless 'China' modules the discount 'Sores' sell to fail regularly...

SO...
John Strenk came up with a 'Stealth' swap so you can run an HEI style module that works with the E-core coils better,
And it doesn't show, so you don't get popped at the 'Emissions Visual' inspections.

You simply GUT the case of the factory module, saving as much of the wire as you can,
And you use the aluminum case as a heat sink for a GM style module ($20-$25) that handles the higher current the E-core coil passes to the module.

-------------------

Since you didn't tell if you have an E-core coil or not, I'm not sure this is your problem.

The cap, rotor, plug wires upgrades WILL NOT increase the load on the coil/factory module,
But the E-core coil swap WILL increase demands on the factory/'Replacement' modules.

---------------------

The swap goes something like this,

Diode Version.gif


The 'Capacitor' and 'Diode' are optional, depending on what ignition switch your vehicle has, and if you hear the ignition in the radio.

Capacitor is from an HEI, and stops radio noise,

Diode will stop the starter motor running 'On' after you let off the key switch.
Not all Jeeps are wired the same,

And since the parts stores no longer stock the early Jeep ignition switch, substituting the GM version,

The diode is sometimes needed to get the vehicle started and running and NOT have the starter 'Run On' when you let the key switch return to 'Run' position.

With this module conversion, you DO NOT need an ignition resistor of any kind, you can feed that E-core coil with full line voltage with no issues,
Just make sure you get the module down on a good heat sink and use heat transfer paste under it, NOT dielectric grease that often comes with the GM style HEI modules.

Bypassing the factory ignition resistor wire is your choice.
Bypassing it adds just a little more to your spark energy, but in most cases, it's not necessary or worth the extra work.

The diode is Radio Shack p/n 276-1141 about a buck each usually comes in a two pack so you can screw up the first time.
 
Torxhead, there are SEVERAL resistors all over the vheicle.
The Ignition Resistor splices into the ignition wire shortly after it comes through the fire wall and proceeds to the positive side of the ignition coil.
The ignition coil resistor wire is 1.5 Ohms.

The 'Brown' resistor wire at the alternator also hooks to that splice for ignition going to the engine, it's either a 10 or 15 Ohms (depening on what alternator your vehicle came with from the factory),

And it's there to keep the alternator 'Excite' terminal on the alternator from 'Back Feeding' the ignition circuit.
The alternator 'Excite' terminal turns 'Positive' (positive voltage) when the alternator starts charging the first time and stays positive until the alternator stops charging when the engine quits turning.

Since it's positive almost any time the engine turns,
And since it 'Sources' at the same feed for the ignition,
It CAN keep the ignition working after you turn the key switch 'Off' (Run On).

The 'Brown' resistor wires chokes the back feed down to a point where it CAN NOT power up the factory ignition once you turn the key switch off,
And that's about it's only function, unless you want to get into the different regulator designs that Delco Remy put into the SI series alternators...
 

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