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Convert Pertronix Pos Ground to Neg Ground?

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Go_Dogs_Go

Go_Dogs_Go

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When I bought my electronic ignition distributer my Sprite was Pos ground and now I want to install an alternator. Has anyone converted the Pertronix Flame-Thrower to negative ground from positive ground? I see a Pertronix igniter kit for sale that is used to convert points to electronic and it looks like the part installed in the distributor. Would that work if I used a Pertronics neg-ground ignitor part in my pos ground Pertronix? Or is the exisiting module in the Pertronix distributor a different part altogether?

Simpler solution maybe: could I simply drop a new plate, points, condensor into the Pertronix distributor and do the standard method of converting the car to negative ground?

I really appreciate your help.
GDG
 
I believe that the Pertronix is different between a positive ground and a negative ground and can not be changed. Either buy or trade for a neg ground one or go to points.
Scott in CA.
 
Positive and negative ground modules are different part numbers and are specific to application. You'll need a new one.
 
GDG, are you asking about changing the coil's polarity or the ignition module's polarity?

Coil polarity is easy to "swap". The ignition modules (as stated above) are designed and made for one ground or the other and they cannot be switched back and forth. You have to buy whichever ground configuration module you need.
 
You might contact Pertronix and see if they can provide a negative-ground module, or tell you which module to get. I have never used their Flamethrower distributor, but if it consists of an ordinary distributor with the module, that should be quite possible. I think it would be a step backward to go back to points.

I will say, this illustrates a point I've made repeatedly: positive ground is fine for a stock car, but as soon as you start adding modern electrical or electronic components, switch to negative ground. At some point you'll almost certainly have to do that, and if you have a lot of positive-ground components, you'll have to replace them.
 
This is what I have found in converting a Pertronix Flame Thrower polarity. Inside the distributor is a plate that contains a module that is either pos or neg grounded. That module is on a plate that sits ontop of the standard 45d5 points plate. At this time I think the distributor can be converted by simply dropping in their Ignitor EI system for the chose polatity. Since if you think about it, it is a new 45d4 distributor complete with the 45d5 points plate. The only difference is the module. And given that it is a standard 45d4 points plate that could accept points or the Ignitor EI system, I think by switching the module using the Ignitor product would work. I'll let you know after I talk to Pertronix or Moss tomorrow.
 
What you describe is pretty much what I'd expect, and you're probably right that it just requires a new module. Still, as you say, it's good to check with Pertronix before dropping $80 for a new module.
 
If I am reading this correctly, I think you may be able to convert it. From my understanding the only thing that affects the grounding is the hall effect sensor. In which case you could just swap those out. They are still $100 though (Moss 222-405).
 
You need an LU-143 Pertronix kit to change out the innards (module) to work with negative ground. It currently has an LU-143P12 positive ground unit installed. The wiring is very different as well, so follow the instructions carefully. If you need a complete new breaker plate with points, I can provide you one until you know you have all the bugs worked out. If any step of the conversion gets missed, a Pertronix unit will burn out in a second or two. Mushroom cloud and all...
Jeff
612-804-55 four three
 
According to Pertronix in the case of GDG versus the Flame Thrower Pos Ground Part Number D1786, the solution is a pertronix part number D500707. I have not yet received mine but I am curious when I get it to find out if it is simply the negative ground ignitor module. MOSS also has a part in stock 143-118(maybe the same thing?) that is not listed in their catalog. So I am curiouser and curiouser about what this part is. I'll be back in almost 2 weeks and hopefully I can post the answer when I return.

Jeff we must have different distributer units. My module is 11AE-12VP2V5 in the pos ground unit and according to Pertronix that is not the part number after all. It also says Carib E O D-57 2 on the ignitor label on the module.

I'll post back when I get the part after my vacation.
Thanks!
 
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