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Coil options for pertronix

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Atrus

Atrus

Jedi Warrior
Offline
OK, so I pulled the coil I am using from the vehicle. I'm slightly ashamed, as I think I have been running this incorrectly. For the record, no pertronix yet, but I'll be ordering it soon.

I wanted to switch to the more modern style of wires, and the stock lucas I had was the other style (wires enter the side of the cap, screw-on connector to coil). Anyway, in my ignorance, I asked a friend who worked at Autozone what they'd have to replace it. He sold me a Chevy 4.3L coil. I put in fresh wiring (old wiring was all hacked up, my job wasn't much better), which means, as far as I can tell, I'd have no ballast or anything.

I just pulled the coil, and I see it says "use with primary resistance wire or external resistor". So, this tells me I completely have been trashing this coil.

I see the flamethrower coils for $30 or so online. Any more frugal suggestions? I suppose I'd prefer to have one that's internally ballasted so I can just plop it right in.

Thanks!
 
What does the Pertronix literature say about ballast? That's the real issue. If you need ballast with it and you have an unballasted coil, you can easily buy a ballast resistor. You probably haven't burned out the coil, but you can check it with an ohmmeter. If you don't have a meter, I strongly recommend those neat little $7 digital jobs from Harbor Freight.

I have a Crane XR700 ignition, which requires ballast. The higher-end XR3000 specifically tells you not to use ballast. I don't know what the Pertronix requires, but it's probably more of an issue with the electronics than with the coil.
 
Quoting directly from the Pertronix instruction leaflet that comes with the unit...

The Ignitor is compatible only with a "points style" coil. 4cyl engines require a minimum of 3 ohms resistance.

If your present ignition system is equipped with a ballast resistor, do not remove it.

Caution: Never use a "HEI" coil with the ignitor. This type of coil will damage the module, cause it to fail, and void the warranty.

...
 
Chris, you brought up the other point I forgot to mention...how do I know if this style is a "points" type or not?

I checked resistance...between the two side terminals, 2 ohms is what I am getting. From either side to the center, I am getting 8.8 ohms.
 
Atrus said:
From either side to the center, I am getting 8.8 ohms.
Click to expand...

That doesn't sound right. From center to case you should get something but from either side to center should be very big resistance.
 
Derf, that's what I thought too - 2 ohms seems to make no sense either, should be 1.5 or 3 from what I have seen. This was using a fairly nice Craftsman multi-meter. Sides, 1.8-2.0. Side to Center, steady at 8.8.

I think I'll just order the flamethrower for the $27 is costs and call it a day. I can just wire the 3 ohm straight in with no resistor, correct?
 
""""""wanted to switch to the more modern style of wires, and the stock lucas I had was the other style (wires enter the side of the cap, screw-on connector to coil). """""

Your only choice when using a side entry cap is spark plug leads that are a solid metal core and 7 mm. Using "modern" spiral core wire or carbon core supressor wire, the wire or carbon core will burn back in very short order, as you dont have room in the cap holes to wrap the core back and use a crimp terminal.

Use a top entry cap and 8mm spiral core wires with 90* boots and terminals on the dist. end so the terminals then will go in the cap sockets.

"""""""I checked resistance...between the two side terminals, 2 ohms is what I am getting""""""""

So use a ballast resistor in the wire from the key to the + terminal on the coil. Pertronics units want 3 ohms
at least when used without an ignition box. When used with a box it doesnt matter.

""""""" I'll just order the flamethrower for the $27 is costs and call it a day. I can just wire the 3 ohm straight in with no resistor, correct? """""""

Correct...........or use your 2 ohm coil and a $3 ballast resistor ....at your corner parts store and youll have all that $$$ to spend on beer.
 
Check the resistance of the leads and meter offset. Connect the ohmmeter leads together--you'll probably see half an ohm or so. So, if you are measuring 2 ohms, and the lead resistance is 0.5 ohms, the coil is really 1.5 ohms. A ballasted coil should be about 3-4 ohms, so obviously that one isn't ballasted.

Some coils have the supposedly grounded end of the secondary connected to a side terminal. I don't know why they do this, but it's done. That would explain the 8 ohms side to the center.
 
Jerry,

If we're looking at $3 or so for a ballast resistor, I'll do it. I was looking online at summit racing and whatnot, and they seemed to be like $20 or more. I thought for the extra few bucks, I'd get the flamethrower. I'll stop in at Autozone this weekend, need to go there for other things anyways. I'm all about extra beer money (since I brew my own!) so thanks!!!

Yup, I currently have 8mm (I think) wires (they are modern-style) with the 90* end on the top-entry cap.

What's the "points-style" deal? How can I be sure that this is the points style?
 
Steve,

Makes sense, didn't think about the lead resistance. I'll check that when I get home.
 
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