Oil vs Epoxy coils.....

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i've always used auto parts oil filled and never had a problem...maybe i've been lucky?
epoxy seems like a good idea.
 
I prefer epoxy because there is zero chance of a leak like oil filled.
If they leak, not only does it make a mess but they fail so I run an epoxy E core and I notice it barely gets warm.
Curious, though, about cracking in the cold. :realcrazy: We see below zero F up here every winter....
 
Had an issue with oil filled stock coil, very rough road and car died. after trouble shooting, found an internal wire broke in the coil. Replaced with off road epoxy and no problem after with factory electronic set up and rough roads. Since moving from Louisiana to Arkansas, have switched to FBO coil and ign box, no problems , but the roads are a lot smoother.
 
There are many variables other than oil and epoxy.
The type of ignition system significantly changes the heat generated in the coil. HEI, type ignitions properly control the coil charge time, filling coil just before use in spark. Coil charge time is typically only a few milliseconds. At idle, a ballast resistor limits the coil current, but not the time, the time between sparks is hundreds of milliseconds. The dwell time with point adjustment reduces the charge time some, and mopar electronic without, heats coil more.

In short, modern epoxy filled coils are designed for use with mode HEI or dwell controlled systems.

Epoxy filled coils have an improved magnetic path, and a more compact design. The compact design, reduces the length of copper wire, reducing resistance and associated wiring.

The canister coils were an improvement over tar filled wooden box coils used on early Fords. Oil circulates, and serves to fill voids for self healing insulation.

Epoxy coils have special manufacturing requirements. Vacuum is drawn when epoxy is filled, to remove bubbles, that make voids. Process control is important, because once potted, bubbles are hard to identify.
 
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There are many variables other than oil and epoxy.
The type of ignition system significantly changes the heat generated in the coil. HEI, type ignitions properly control the coil charge time, filling coil just before use in spark. Coil charge time is typically only a few milliseconds. At idle, a ballast resistor limits the coil current, but not the time, the time between sparks is hundreds of milliseconds. The dwell time with to point adjustment reduces the charge time some, and mopar electronic without, heats coil more.

In short, modern epoxy filled coils are designed for use with mode HEI or dwell controlled systems.

Epoxy filled coils have an improved magnetic path, and a more compact design. The compact design, reduces the length of copper wire, reducing resistance and associated wiring.

The canister coils were on improvement over tar filled wooden box coils used on early Fords. Oil circulates, and serves to fill voids for self healing insulation.

Epoxy coils have special manufacturing requirements. Vacuum is drawn when epoxy is filled, to remove bubbles, that make voids. Process control is important, because once potted, bubbles are hard to identify.
I actually understand epoxy, as I used to work at Honeywell and filled prox switches with epoxy. We baked them in a oven at 150 degrees to get the bubbles out, then finish filling the switch.
Anyways, I've never run an epoxy coil on a older mopar before and was wondering if there was a benefit. Seems by your post, epoxy coils are meant for HEI ?? I don't have HEI, so perhaps I should stick with the oil filled coils? I was only thinking epoxy coil for heat reduction and long life.
 
I actually understand epoxy, as I used to work at Honeywell and filled prox switches with epoxy. We baked them in a oven at 150 degrees to get the bubbles out, then finish filling the switch.
Anyways, I've never run an epoxy coil on a older mopar before and was wondering if there was a benefit. Seems by your post, epoxy coils are meant for HEI ?? I don't have HEI, so perhaps I should stick with the oil filled coils? I was only thinking epoxy coil for heat reduction and long life.
150F is not very hot, underhood temperatures can reach +200F, and coil temperature rise above that. Oil circulates with convection, epoxy does not, it is the enamel on the windings that fails, shorts windings and coil is damaged.

Modern coils have a primary resistance of about 0.5 Ohms, standard canister coil about 1.5 Ohms. Changing to modern coil in ballast system results in increased current, that may fail the ignition box. The HEI conversion eliminates the ballast, and properly control the coil charge, that is how to have a cooler, more efficient coil and ignition.
HEI conversion is not difficult, if you have electrical skills. If you want an easy to install system with support, TrailBeast of this forum sells conversion package.
 
150F is not very hot, underhood temperatures can reach +200F, and coil temperature rise above that. Oil circulates with convection, epoxy does not, it is the enamel on the windings that fails, shorts windings and coil is damaged.

Modern coils have a primary resistance of about 0.5 Ohms, standard canister coil about 1.5 Ohms. Changing to modern coil in ballast system results in increased current, that may fail the ignition box. The HEI conversion eliminates the ballast, and properly control the coil charge, that is how to have a cooler, more efficient coil and ignition.
HEI conversion is not difficult, if you have electrical skills. If you want an easy to install system with support, TrailBeast of this forum sells conversion package.
I will not be going HEI anytime soon. I know Trailbeast sells them. The fact is, I have next to zero issues (and I have owned many, many mopars) with the factory Chrysler electronic ignition. I was wondering if there was an advantage of an epoxy coil over oil filled. But it sounds like you don't think either should be used with the factory set up. I've used Accel coils with them, but I was looking into the Pertronix shown in the first post.
 
In all my bla-bla I forgot to look at the coils in question, sorry. The first coil is a $20 coil with a $14 sticker saying Pertronix.
The second is unkown, they seem to leave out specs.
Coils rarely fail. If your original sparks blue, it might be better and more reliable than either.
 
In all my bla-bla I forgot to look at the coils in question, sorry. The first coil is a $20 coil with a $14 sticker saying Pertronix.
The second is unkown, they seem to leave out specs.
Coils rarely fail. If your original sparks blue, it might be better and more reliable than either.
Do you know who sells these $20 coils (40000 volts/1.5 ohm) without the 14 dollar sticker?
And why this kit states only to use this coil. Not the Accel, MSD or Mallory coil.
FBO Ignition Systems
 
Try your local auto parts store.
40kV is sales hype. Peak secondary voltage is limited by 1. Spark gap in conjunction with combustion dynamics, or 2. Coil turns ratio times peak primary voltage, limited by collector to emmiter clamp voltage, whichever is least. The 40kV coil with high turns ratio, is less desirable for spark current due to impedance mismatch, and higher secondary resistance.

Buy whatever you want, I am only trying to provide information about specs, and how they relate to ignition performance.
 
Seeing this thread reminds me of something a old racer once said. Oil filled coils need to be mounted horizontally so that the 12 volt wires are at the bottom. Internally the wires and connectors are submersed in oil to keep tham from burning out. He was speaking mostly about HP coils like the old Accel Super coil but not a bad idea for any coil.
 
My Accell sq.top, plastic cased, oil-filled, baking just above the header, take-no-prisoners coil, has been happily ticking away, sometimes on the Orange ECU, sometimes on any-old-ecu, and since 2004 on a JACOBs ECU, for about 125,000 miles.If it ever gives up, I will buy another exactly the same, and I don't care how much they cost. That thing is a reliable as skunk-oil stinks.
 
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The Chromebox I first was using on the Barracuda was per the MP Book best matched with the Accel Supercoil. I had that coil mounted upright, to the firewall. I got a few years out of it, at least 20 K miles. Then I had smelled oil on a trip, and it turned out to be the coil had started seeping oil around the top.
 
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