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Not sure if this has been addressed: need to use resistor spark plug wires, not solid wires. I ruined a Pertronix with my solid core wires. Just sayin' . . .
 

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Discussion Starter · #22 ·
Uhhmm .....coil?
I wondered the same thing. I checked with Summit tech and Pertronix tech regarding the coil I am using. Both said that the coil was acceptable for their unit and should not be a problem. Both need 12v at the coil.

I guess I am a glutton for punishment. Summit has been golden on refunds for the 2 units I have blown up, so I ordered a FAST XR-i unit and installed it last night. The Fast unit is half the price of the comparable Pertronix unit. Haven't started it yet. Will do that later today after it warms up a little. I don't like to run it in the shop. The FAST unit requires a ballast resistor. I had to wire that back in, along with the R starter wire to bypass the BR. I ran my setup by FAST tech with values for coil primary resistance and ballast resistor resistance. They said it should be hunkey dorey. We will see later today. I also received the NOS points and condensers. They will go in the glovebox. I can put them back in alongside the road if necessary,
By the way, the spark plug wires are Taylor suppression wires.
I would like to request that everybody cross their fingers for me today. I need all the help I can get.
 

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There seems to be two types of ignition systems talked about in this thread. One is a point type along with a solid state points replacement. They yield the same thing, one is mechanical the other is solid state. There is really no advantage of the solid state over a WELL PERFORMING points ignition that would enhance the spark or increase dwell time at higher RPM’s.

The other is a performance enhancing HEI type which uses a magnetic pickup in conjunction with a module of some sort such as GM module from HEI (big diameter) distributor. This will enhance spark and increase dwell at upper RPM’s. I also runs on full 12.7 to 14.3 volts, no resistor.

I have found there a few presentations on the interweb where guys have added an HEI module and Ford or Mopar pickups to trigger a modified stock ignition system. Check them out.

The modern Delco “E” core coils has a low ohms resistance to increase effectiveness and efficiency over a standard oil filled round coil. A concern I had while using HEI module is heat build up. The lower impedance “E” core coil is desirable in that regards.

As pointed out I built my own small diameter HEI distributor converting the stock distributor in 3 of my cars. I posted some of the results, previously. There are small diameter distributors you can buy. But quality is not inherent in all of them. One that I purchased had excess clearance in the block and wiggled when tightened down and engine running. Original stuff while not the most performance oriented at least it fits well. Thus my decision to modify a stock 60’s vintage cast iron GM Chevy distributor to HEI.

All that aside, one needs to understand the points elimination solid state points replacements does nothing to increase power/performance. In fact I’m pretty much convinced the points is better in street performance and reliability. Now HEI is fairly reliable when done as GM did the big diameter distributor. Parts have to be matched and heat & electronic emissions have to be accounted for. Now I have been using “E” core coil, 8MM solid core copper plug wires and non resistor spark plugs without issues. But I’m inclined to believe that part placement has a lot to do with it.

One thing I wish to share is that not all HEI modules are equal. In fact some are junk even before taken out of the package.
526942
 

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Mopar and Ford used external amplifier style modules that were troublesome early on. Ford seemed to suffer from connection issues, Mopar failures were untraceable for me. GM modules were quite good until subjected to excessive heat. Pickup coils suffered from insulation on the wires becoming hard and inflexible causing variable resistance and thus additional heat. The vacuum advance moving would eventually break the wires. In most drag situations, the vacuum advance was not used so that issue became almost non existent. I had an Accel conversion in the late 70s that used a trigger wheel that mounted under the rotor and an inductive pickup. On a dist machine, it was flawless. For some reason, one set of trigger fingers failed to work and it was dead on one cylinder. This was after a few months and they wouldn't warranty it or sell me just that piece. I had to buy the whole thing again. I went to Mallory and MSD next and have shunned Accel since.
 

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Discussion Starter · #25 ·
I ordered a FAST XR-i unit and installed it last night. The Fast unit is half the price of the comparable Pertronix unit.
Well, to continue this saga, I got it running with the FAST XRi unit. It ran terrible. Farted and backfired. I immediately took it out and installed points and condenser without moving the distributor. It runs like a champ. Go figure. 2 pertronix conversions, 1 summit RTR distributor, 1 chinese distributor, 1 Fast XR-1. All going bad within 2 months. Now, I'm not blaming any of these companies because there definitely is a pattern here. There is something going on, but it is darn funny that the 60+ year old technology works when nothing else will.
 

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Would be neat if you could put it on an Oscilloscope when you fire it up and take a movie of the screen. Also what the coil supply voltage is doing.
 

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It’s possible the coil intermittently grounds out. That will not cause points to fail but not so much harmless with electronics. Also any alternator AC leakage is also bad for electronics where points can tolerate it. Not saying these are the cause but possibility’s.
 

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Discussion Starter · #28 ·
It’s possible the coil intermittently grounds out. That will not cause points to fail but not so much harmless with electronics. Also any alternator AC leakage is also bad for electronics where points can tolerate it. Not saying these are the cause but possibility’s.
I don't think it is possible for the coil to be grounding out unless it is internal.
I have wondered if alternator output spikes might have something to do with it. I wouldn't know how to check for either one. I am using a one wire ALT and an Odyssey battery that seems to carry more volts than a standard lead acid battery.
 

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Try checking alternator output voltage at high idle at the output stud with a voltmeter. 14.7V DC max. Does the voltage fluctuate? Good grounds are a must. Engine to frame, frame to body, battery to engine, with a fiberglass body, grounds have to be supplied to gage cluster, light bezels etc. Use braided ground straps. Not just wires. My friends street rod had bad grounds and did the same thing you are experiencing. His voltage was spiking to 18 or 19 VDC. It really showed up driving down the road with head lights on. He actually burnt out Zenon head lights, 3 Mallory Unilite Modules, and an electronic Tach. Added grounds and installed new Pertronics points to solid state conversion 3 years ago and still runs great. We did not replace or mess with the 3 wire 100 amp 10 SI alternator. Output voltage now maxes out at 14.3 VDC and stays steady.
 

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Don't think this is it but it's worth mentioning: Ford had issues with coils in the late 70s thru thru mid 80s with coils manufactured with not enough oil in them. Sudden turns would slosh internally and change the whole resistive value enough to make it blank for a moment. Long enough for the engine to die but recover well enough to restart immediately. Points distributors didn't seem to matter but the DuraSpark electronic Ignition did. Hammer a module over time. We weighed them out to find culprits. I am still a fan of the good old oscilloscope plus checking voltage on both sides of the coil. And is the polarity correct from coil to distributor? They will run reverse polarity on points but electronic is another animal. Just an FYI for those reading and learning.
 

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One wire alternator is fine for a tractor but cars where drain varies ...not so much. An original style 3 wire set up is far better for system voltage/current control.

Yes internal short in oil filled coil can ground it out.
 

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Discussion Starter · #32 ·
Try checking alternator output voltage at high idle at the output stud with a voltmeter. 14.7V DC max. Does the voltage fluctuate? Good grounds are a must. Engine to frame, frame to body, battery to engine, with a fiberglass body, grounds have to be supplied to gage cluster, light bezels etc. Use braided ground straps. Not just wires. My friends street rod had bad grounds and did the same thing you are experiencing. His voltage was spiking to 18 or 19 VDC. It really showed up driving down the road with head lights on. He actually burnt out Zenon head lights, 3 Mallory Unilite Modules, and an electronic Tach. Added grounds and installed new Pertronics points to solid state conversion 3 years ago and still runs great. We did not replace or mess with the 3 wire 100 amp 10 SI alternator. Output voltage now maxes out at 14.3 VDC and stays steady.
Yes, that is what I was thinking could be the problem. I will check the ALT output 1st thing. That could very well be it.
I know the importance of grounds in a 12 V system. I think that my ground system is very good. Built with welding cable bellhousing to frame, then 10 ga, wire to body and dash. All lights have a ground to frame, even the radiator. I have been thinking about grounding the heads and manifold and even the distributor body just to make sure. It wouldn't hurt to check all my grounds though.
Thanks
 

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Discussion Starter · #33 ·
One wire alternator is fine for a tractor but cars where drain varies ...not so much. An original style 3 wire set up is far better for system voltage/current control.
LOL! As I'm sure I mentioned I am pretty electrically challenged. The 1 wire hook up is what made it attractive to me. I'm sure you are correct as to the function of the 3 wire ALT. If 1 wire was good, GM would have never used 3 wires. :) As I said, I will check the output and see where I am.
 

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For electronic modules impedance of the coil is important. Impedance speaks to current flow where higher impedance forces a reduction while lower allows more.

The problem is similar to setting up a stereo where the amp output for the speakers need to match the speaker coil input impedance. An automotive ignition is matching the module impedance to that of the ignition coil. For solid state units in particular the transistors will run hot if the speaker impedance is below the spec of the amp simply because there is a higher current flow which causes the power transistors to run hot which eventually lets their smoke leak out then they stop working.

The electronic module of an ignition system is working in a similar manner with its coil. So what is safe with solid-state components is to run a matched or higher impedance on the load side.

This gets into your B+ voltage as well, running 14.75 volts is on the high side for continuous out put. The alternator voltage higher than the battery’s fully charged rest voltage is used to recharge the battery, as the battery is recharged the regulator should curve the alternator output back to the battery’s standing voltage. Beyond that the alternator should only increase output as operating loads demand more current that the battery can supply, this without the alternator, will be seen as a voltage drop. For the most part an operating voltage not exceeding 13.5 is acceptable, but the safe zone for an automobile is really pretty limited long term excursions heading toward 15 volts can start eating parts, this is not a case where more is better.

The alternator output is typically rather dirty in that it contains a wave form of some type where the battery doesn’t it produces a clean straight line voltage. The automotive charging system essentially uses the battery as an electrolytic capacitor to clean up stray wave forms. But you can assume that any line voltage higher than the battery’s standing full charge voltage has some dirty waves in it. These technically should be a ripple current on top of the DC not an AC where the voltage is cycling between positive and negative. But the question remains as to why the constant high voltage you see and what are the ripple wave forms.

This on the face of things is pointing at the alternator as the likely source of the ignition problem by its delivering an excessively high voltage that probably looks like a babbling brook instead of a placid pond with some soft breeze induced ripples on its surface.

Bogie
 

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Discussion Starter · #35 ·
For electronic modules impedance of the coil is important. Impedance speaks to current flow where higher impedance forces a reduction while lower allows more.

The problem is similar to setting up a stereo where the amp output for the speakers need to match the speaker coil input impedance. An automotive ignition is matching the module impedance to that of the ignition coil. For solid state units in particular the transistors will run hot if the speaker impedance is below the spec of the amp simply because there is a higher current flow which causes the power transistors to run hot which eventually lets their smoke leak out then they stop working.

The electronic module of an ignition system is working in a similar manner with its coil. So what is safe with solid-state components is to run a matched or higher impedance on the load side.

This gets into your B+ voltage as well, running 14.75 volts is on the high side for continuous out put. The alternator voltage higher than the battery’s fully charged rest voltage is used to recharge the battery, as the battery is recharged the regulator should curve the alternator output back to the battery’s standing voltage. Beyond that the alternator should only increase output as operating loads demand more current that the battery can supply, this without the alternator, will be seen as a voltage drop. For the most part an operating voltage not exceeding 13.5 is acceptable, but the safe zone for an automobile is really pretty limited long term excursions heading toward 15 volts can start eating parts, this is not a case where more is better.

The alternator output is typically rather dirty in that it contains a wave form of some type where the battery doesn’t it produces a clean straight line voltage. The automotive charging system essentially uses the battery as an electrolytic capacitor to clean up stray wave forms. But you can assume that any line voltage higher than the battery’s standing full charge voltage has some dirty waves in it. These technically should be a ripple current on top of the DC not an AC where the voltage is cycling between positive and negative. But the question remains as to why the constant high voltage you see and what are the ripple wave forms.

This on the face of things is pointing at the alternator as the likely source of the ignition problem by its delivering an excessively high voltage that probably looks like a babbling brook instead of a placid pond with some soft breeze induced ripples on its surface.

Bogie
I'm gonna hafta read that a couple times. The end result is that an errant ALT could be my problem. I will test for what I am getting from the ALT for sure.
 

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I'm gonna hafta read that a couple times. The end result is that an errant ALT could be my problem. I will test for what I am getting from the ALT for sure.
Easy to rule out. Disconnect the Alternator and run on a good charged battery with no other electrical accessories running. Surely you can run it long enough to see. I am still suspect of voltage at the coil and polarity correct and then perhaps a faulty coil at temperature. I like Mallory stuff myself. They have been quality for the 40 plus years I've bought it and the older stuff is no different.
 

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Sorry. This might end up long.
Long is OK, but would be easier to read with multiple paragraphs. :)

Did you ever get a chance to check alternator output voltage? I once worked on a car with a GM 10-SI that put out around 16 volts! Fixed it with a new regulator. Fortunately the HEI ignition was not damaged, probably because whoever installed the distributor did not bypass the ballast resistor, which was actually a resistance wire in the under-dash harness. Amazingly, the battery and light bulbs weren't damaged, but the insulation on adjacent wires in the harness was starting to melt.
 

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Once you get the charging in line you will want to get rid of the line resistor. See HEI needs a full 12 to 14.2 volts to function correctly. Infact less volts say 9 or 10 can cause the module to over heat as it attempts to feed coil.

HEI needs a 12 gauge or better size feeding it to coil. Look at GM vintage 74’s and up the wire on coil positive is 12 gauge or bigger. Some might even use a relay to insure adequate power, which I think is a good practice.
 

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Be sure you have a single wire and nothing spliced together plus good connections at each end. I like to find a fused space in the fuse box to feed it with 10 gauge with a crimp style connector that is soldered after the crimp and double the shrink tube at each end.
Overkill but never an issue either.
 

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For electronic modules impedance of the coil is important. Impedance speaks to current flow where higher impedance forces a reduction while lower allows more.

The problem is similar to setting up a stereo where the amp output for the speakers need to match the speaker coil input impedance. An automotive ignition is matching the module impedance to that of the ignition coil. For solid state units in particular the transistors will run hot if the speaker impedance is below the spec of the amp simply because there is a higher current flow which causes the power transistors to run hot which eventually lets their smoke leak out then they stop working.

The electronic module of an ignition system is working in a similar manner with its coil. So what is safe with solid-state components is to run a matched or higher impedance on the load side.

This gets into your B+ voltage as well, running 14.75 volts is on the high side for continuous out put. The alternator voltage higher than the battery’s fully charged rest voltage is used to recharge the battery, as the battery is recharged the regulator should curve the alternator output back to the battery’s standing voltage. Beyond that the alternator should only increase output as operating loads demand more current that the battery can supply, this without the alternator, will be seen as a voltage drop. For the most part an operating voltage not exceeding 13.5 is acceptable, but the safe zone for an automobile is really pretty limited long term excursions heading toward 15 volts can start eating parts, this is not a case where more is better.

The alternator output is typically rather dirty in that it contains a wave form of some type where the battery doesn’t it produces a clean straight line voltage. The automotive charging system essentially uses the battery as an electrolytic capacitor to clean up stray wave forms. But you can assume that any line voltage higher than the battery’s standing full charge voltage has some dirty waves in it. These technically should be a ripple current on top of the DC not an AC where the voltage is cycling between positive and negative. But the question remains as to why the constant high voltage you see and what are the ripple wave forms.

This on the face of things is pointing at the alternator as the likely source of the ignition problem by its delivering an excessively high voltage that probably looks like a babbling brook instead of a placid pond with some soft breeze induced ripples on its surface.

Bogie
If it is a single wire, most I have seen are almost always closer to higher output operation than generally needed. Most tractor guys are points or diesel plus they run in a fairly harsh environment, i.e. rebuilt more often and battery(s) replaced in 2 years not 5 or 7. But the paramount issue being pointed out by all is, electronics need clean sine wave power for proper operation and longevity. The days before electronics didn't matter so much.
 
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