Ignition question: 85 GT w/351W swap.

[dagassa]

Hey all!

A while back, I picked up a one owner 85 Mustang GT with a 351w swap (rebuilt bottom end) from a 94 Lightning. I want to do some work on the ignition but given that I have a mix of two vehicles, I'm a little foggy on the path forward? The ignition box is a stock Motorcraft Duraspark while the distributor "appears" to be a Duraspark II unit. The coil is a Motorcraft D5AE-12029 AB.

Initially, I wanted to just put a new coil in and was thinking MSD Blaster 2. Where I'm struggling is that since the ignition is a Duraspark, I'm told that it would require a ballast resistor. I chased the wires from the ignition to the distributor and I did not see a resistor in place. I'm guessing that it's somewhere else in the wiring? In any case, if I put an MSD coil in, do I or do I not need to add the ballast resistor?

Also, if there is no simple answer to the question, would there be any difficulty in just swapping out the Duraspark ignition for an MSD6AL with a Blaster coil? Any help is appreciated!

[ashley roachclip]

The resistor is in the wiring to the coil .
You do not need to add one for the MSD coil .
Factually , the Duraspark and factory coil is perfectly fine for your application.
I have run both , the Duraspark , and MSD 6AL.
I had no problem with either .
I like the MSD, because I can set a different red line .
My engine spins to 7500 with ease, and has power all the way.
I like to set the rev limiter to different levels , for different reasons, autocross , drag racing , when my daughter and son in law, drive the car .

[dagassa]

The resistor is in the wiring to the coil .
You do not need to add one for the MSD coil .
Factually , the Duraspark and factory coil is perfectly fine for your application.
I have run both , the Duraspark , and MSD 6AL.
I had no problem with either .
I like the MSD, because I can set a different red line .
My engine spins to 7500 with ease, and has power all the way.
I like to set the rev limiter to different levels , for different reasons, autocross , drag racing , when my daughter and son in law, drive the car .

Thanks for your response! I'm curious though as to why all the online retailers (Summit, LMR, Jegs etc) say that the Blaster 2 coil that works with the 85 Mustang is the MSD 8203 which comes with the ballast resistor? I've looked at the wires from the ignition to the coil and I didn't see anything that resembles a resistor inline? Thoughts? Thanks again!

[ashley roachclip]

Look at a copy of the Electrical manual from Ford , you will see what I am saying .
They send the resistor as part of the package , so you dont have to buy it extra
Should you decide to go with the MSD set up, make your self a small harness , to plug into the factory , rather cut up the one you have .

[dagassa]

Look at a copy of the Electrical manual from Ford , you will see what I am saying .
They send the resistor as part of the package , so you dont have to buy it extra
Should you decide to go with the MSD set up, make your self a small harness , to plug into the factory , rather cut up the one you have .

Is this the Ford diagram you're referring to? If so, I will have to re-trace the wiring because I didn't see the resistor the first time I looked.

[ashley roachclip]

The resistor wire that the factory used looks like any other wire .
There is no big bump or ceramic connector .

[dagassa]

The resistor wire that the factory used looks like any other wire .
There is no big bump or ceramic connector .

Thanks for all your input! It is appreciated! I decided to just upgrade the electrical. Bought an MSD6AL-2 and a Blaster 2 coil. I was wanting a Rev Limiter anyways.