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Discussion Starter #1
When I got my car it had an electronic ignition in it (unilite), on the way home a pos (+) wire touched the body, and blew the ignition...when I got it i put points in it, I drove it around for about 2 months, then the points burnt up (actually the points looked fine, i think it is the condenser that went bad)...I put new ones in, but I am afraid to drive it around, i dont want to get stuck somewhere. The new points are working, but i dont know for how long. Anyone have any ideas what burnt the points so quick?
 

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Someone probably eliminated the resistor wire when they installed the Unilite. The wire that supplies voltage to the positive terminal of the coil is a resistor type that reduces voltage to prevent the points from burning. Actually, there are two wires on the positive coil terminal, but one feeds voltage only when you are cranking the engine (the one from the starter solenoid). Most electronic ignition systems require a full twelve volts to operate efficiently. All you need to do is to install a ballast resistor in the wire that feeds voltage from the ignition switch run circuit. A two terminal Chrysler type will do the job. Just install it in series.
 

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Wow i am very surprized you went back to points any how my self i just put hei on my 66 396 because i was afraid points would let me down i guess different stroks for different folks.
 

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In 40+ years driving, points have never let me down. Driven points cars to electronic cars 10:1 miles. Electronic has left me sitting at the side of the road several times. Not averse to progress or change--just my experience. For what it's worth. My $0.02
 

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Discussion Starter #5
here is my setup...



Is HEI reliable?, is it expensive?, and do you get the same preformance vs. points or electronic?

[This message has been edited by 69_Malibu (edited 06-25-2000).]
 

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69_Malibu,

That's a not a good set-up.

You want the wire leading from the solenoid (R terminal) to go directly to the positive terminal on the coil. That way when you start the car, the solenoid contacts engage giving that wire a full 12 volts that should go to the coil to aid in starting. You have "the full 12 volt line" wired into the ballast resistor. Not good, this will drop the voltage during cranking which is the opposite of what you want.

It's during the running of the engine you want the voltage drop to the (+) terminal on the coil. If you have the resistor wire, why do you need the ballast resistor??? The ballast would only be needed if the resistor wire was NOT there or something was wrong with it (giving a full 12 volts the whole time).

What voltage are you meausuring when the engine is running at the + terminal on the coil. It should be less than 12 volts to make the points last longer. The ballast resistor is only needed if you have a regular wire from the ignition circuit, as it drops the voltage just like the factory resistive wire would have done to prevent point wear.

I'll post a pic in a little bit.

Joe
 

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Hope that helps.

You see you only need the ballast if you are constantly getting 12 volts (during the normal engine running) at the (+) side of the coil. This is what burns up the points. If you have the factory resistor wire and it still works, just connect it back to the (+) terminal of the coil.

In my picture, I show a regular wire going from the ignition on circuit (I'm assuming that's what the former owner might have done since electronic ignitions require a full 12 volts all of the time). Don't short your solenoid wire and resistive wire together before the ballast.

BTW,

Nothin' wrong with points, I love modern technology but also fear it as well. I'm not going to be stranded in the middle of nowhere because a small silicon-based semi-conductor decides to crap out!

The '70 always been run on points!
http://home.netcom.com/~radiojoe/restore.html

Joe

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"Yes, I'm still workin' on those Chevelle radio pages!"

[This message has been edited by Coppertop (edited 06-25-2000).]

[This message has been edited by Coppertop (edited 06-25-2000).]
 

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Discussion Starter #8
Ok, I should have mentioned a few more things, I have a Ford starter solinoid (the guy who owned it before me put it in). Also it is the factory installed resistor wire, however, at some time some one cut it about 10 inches before the coil, it is re attached, but does this affect the resistance? My friend masured it and said that i still need the ballest resistor. What should the Ohms and Voltage be before and after the ballast resistor? ohh and the (-) wire from the coil is attached to the points.

[This message has been edited by 69_Malibu (edited 06-25-2000).]
 

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69_Malibu, you are Ok until the yellow wire at the resistor, move it from the ballast resistor to the coil plus terminal, and you will be OK.

What I am saying is the yellow wire from the I terminal, Ford solenoid goes directly to the coil plus term, not through the resistor wire. The way you have it, the bypass start wire (yellow, I) is resisted, doesn't want to be, wants to supply a full battery voltage to the coil for easier fire up with point systems.

Coppertop's system is correct for GM starter mounted solenoid only systems.

Ford I term and GM R term do the same function on each-other.

GM soleniod has to be bridged from large battery cable terminal to R term for Ford solenoid useage.

BTW, for those systems that have no ballast resistor in line (wire changeovers/retro-fits and new point systems), the NAPA ICR13 is the proper in-line ceramic resistor to use for GM point ignition systems.

[This message has been edited by IgnitionMan (edited 06-25-2000).]
 

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I-Man,

Have a question for you,

What kind of voltage should I be seeing at my coil (+) terminal when the engine is running normally (not cranking).

I'm getting 11.63 volts at the (+) terminal, at 1000 rpms (batt. voltage approx. 14).

That seems kinda high? What is considered okay to prevent point wear?

This is a stock '70 Malibu with points/original coil and wiring.


Joe

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[This message has been edited by Coppertop (edited 06-25-2000).]
 

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<BLOCKQUOTE>quote:</font><HR>Originally posted by JJ'65:
In 40+ years driving, points have never let me down. Driven points cars to electronic cars 10:1 miles. Electronic has left me sitting at the side of the road several times. Not averse to progress or change--just my experience. For what it's worth. My $0.02<HR></BLOCKQUOTE>


Im with you JJ. I would take points over electronic anyday.

If anything is going to let you down, it would be the electronic, not points.

And for everyone that likes electronic, you just haven't gotten stranded yet when the module decides to take a crap leaving you God knows where with your thumb up your...

No offense guys,
but better carry a spare module.



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Coppertop, the idle voltage can be as high as you see on your application. Remember that the idle speed lets the coil saturate with more voltage per event than higher rpms do, so as the coil is re-charged, the time it to do so is longer, uses more current, voltage.

As engine rpms increase, time between charging events shortens, and the current, voltage need is reduced as well.

When I look at one of my HEI conversions on the distributor machine, the voltage stays constant at about 14,60 volts, but the amperage draw is up around 4.0 at idle, from coil saturation time. As I rev the distributor machine up, the volts stay same, but the amperage drops to 1.70 at full rpms.

Remember, HEI has no resistor, so voltage will stay same. In a point system, it all comes down to what the coil needs to fill it electrically. I would think you would see a lowering of voltages as rpm increases, to maybe arouond 9.50 to 10 volts or somewhere near there.

Check it out and see if I am correct, it's what I found on point distributors I have messed with over the years.
 

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IgnitionMan: Your information on current draw is really interesting. With a max draw of about 4 amps and a high speed draw of less than 2 amps I become puzzled why GM used such heavy gage wiring to power the HEI's. Is there something different that you are doing with your conversions to make them use less current? I had assumed that if GM was using such a heavy +12 wire that the HEI must really be sucking up the amps. Got any ideas on why they did what they did?
 

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I use stock point caps and rotors, so all my conversions use a remote out-of-cap coil. I recommend oil-filled coils for all applications, and won't use an epoxy coil for my conversions, no matter who says they are better. It has NEVER been proven to me that an epoxy coil has ever been better than an oil filled one.

The stock GM coil in cap coil is epoxy filled, uses more current than an oil filled one, needs bigger load carrying ability as coil gets hot and makes it's own greater internal resistance = bigger wire.

Look at the stock coil in cap HEIs, the module power supply feed wire isn't 10 or 12 guage, only the one going to the unit is, for the coil they use.

I use a 14 guage wire for all my conversions that need a converted or new feed wire, and haven't seen any loss of revs from smaller than GM feed wire size. I also test all my systems before they leave here, with a 16 guage feed wire to both coil and HEI module on my distributor machine/tester, and test to 8,500 rpms, without spark fall-off. I have a see-through thick plastic pressure chamber to view the firing ends of the plugs I built and scope to test system under pressures encountered in the combustion chambers, for accuracy and output.

I have one guy who refuses to change his 20 guage feed wire from them run side of the ignition switch to the coil in his shoebox Nova with very hopped-up 283, and revs his small-body HEI to 7,400 rpms a lot. Scares me, but it works. He has a MSD Blaster II coil and one of my every day driver, performance small HEI setups, spiral core wires, gaps plugs at .045. The feed wire doesn't get any hotter than ones I have felt for large cap HEIs. Strange.
 

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Here's a little electronic theory for everyone...

The ignition coil can be thought basically as an inductor.

If the voltage stays constant across an inductor, but the frequency increases, the current decreases. The frequency has an inverse relationship to the current thru an inductor.

What I-Man says is totally correct and a great real life example of this. As RPMS increase, so does the frequency of the "on/off" of voltage thru the coil. As the frequency increases, naturally the current draw will decrease.




Thanks I-man.

Joe


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"Yes, I'm still workin' on those Chevelle radio pages!"
 

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Nothing personal, Igman. But it is you who has made it personal by your attitude and name calling. And it is not welcome here on TC. Your posts have been fairly well respected here but you have now lost much of that respect. You had no reason to take the tone you did in the intake/head thread. And your comments on this thread is what TC is NOT about. I only hope, my friend, if you are still my friend, and I hope so, that you will not take this attitude and tone again. I think I can speak for other TC members when I say we don't need that. This is a class site and what you have said is not classy. Call me anything you like, it doesn't bother me. I'll just feel even more sorry for you. But just don't do it to anyone else.

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