What did I do wrong here (HEI Conversion)

[zombezoo]

Purchased:
Pertronix 44011 Flame-Thrower III Ignition Coil, 45,000 Volt 0.32 Ohm, 12 Volt, Black

HEI distributor mount

Delphi DS10071 Ignition Control Module

All brand new.

I removed the existing ballast resistor, tied ignition 1&2 together and wired to coil positive and hei module
Coil negative to hei module
Electronic distributor field wires to the other two terminals.

I did not increase the gap on the plugs yet (problem?)

Car started and ran great.

Started and stopped the car probably 30 times while getting other items setup. Idled car for at least 30 min on several occasions, no issues.

Today was first extended drive, made it about 40 min and car backfired and died on the road. No spark.

Coil has failed spectacularly. Crack across the wire end, sprayed it's oil out all over.

Coil and hei module apparently dead.

Swapped for original Mopar coil and spare hei module, car runs, just did that for 2 min to get back into the driveway.

Did I get the wrong coil?
Can bad hei module fry the coil?
Did the stock plug gap do this?

 

[Don Frelier]

I think the coil went bad and then the hei module.
The instructions for the coil read to keep the ballast resistor unless you are using the matching pertronix ignition amplifier or capacitive discharge.

Caution: Flame-Thrower III 0.32 coils should not be used with the (original)
Ignitor, Ignitor II or point type ignition system. Flame-Thrower III coils are only
compatible with Ignitor III ignition systems, and most Capacitive Discharge (CD)
systems that control the dwell period, or limit the current. (12volt negative ground
systems)
HIGH PERFORMANCE COIL
INSTALLATION INSTRUCTIONS
* Legal in all 50 states and Canada
CARB E. O. #D-57-17
BALLAST RESISTOR or RESISTANCE WIRE
The ballast resistor needs to be removed if the Flame-Thrower III coil is used with the
Ignitor III, or any Capacitive Discharge (CD) system that controls dwell or limits the
current. This only applies to Ignitor III, or Capacitive Discharge systems.
1. To remove a ballast resistor (normally white ceramic blocks 3 to 4” inches long),
disconnect all wires on both ends of the ballast resistor. Remove the resistor from
the vehicle and splice the wires together at a single point.
2. To remove a resistance wire, trace the coil power wire, which was previously
connected to the positive coil terminal, back to the fuse block. Bypass this wire with
a 12-gauge copper stranded wire.
If the vehicle has a ballast resistor or resistance wire, and is not equipped with
one of the systems mentioned above, the ballast resistor should not be removed.

Spark plug gap was not a contributor.

A stock coil may not fare well either without a ballast resistor. But better than a low resistance primary like the flamethrower.

 

[pnora]

Purchased:
Pertronix 44011 Flame-Thrower III Ignition Coil, 45,000 Volt 0.32 Ohm, 12 Volt, Black

HEI distributor mount

Delphi DS10071 Ignition Control Module

All brand new.

I removed the existing ballast resistor, tied ignition 1&2 together and wired to coil positive and hei module
Coil negative to hei module
Electronic distributor field wires to the other two terminals.

I did not increase the gap on the plugs yet (problem?)

Car started and ran great.

Started and stopped the car probably 30 times while getting other items setup. Idled car for at least 30 min on several occasions, no issues.

Today was first extended drive, made it about 40 min and car backfired and died on the road. No spark.

Coil has failed spectacularly. Crack across the wire end, sprayed it's oil out all over.

Coil and hei module apparently dead.

Swapped for original Mopar coil and spare hei module, car runs, just did that for 2 min to get back into the driveway.

Did I get the wrong coil?
Can bad hei module fry the coil?
Did the stock plug gap do this?


View attachment 1828112

Never seen a failed coil look like that. My opinion is that the coil was damaged when it was installed. I am not saying you damaged it when installing. It could of been dropped somewhere along the line.

 

[zombezoo]

Thanks all, I thought I had read that coil could be used without a resistor, I will go back through the posts and pick a different coil.

The coil did come with a dent in the base from shipping, perhaps it contributed to the failure.

 

[Fran Blacker]

Thought you were suppose to use E-core coils?

 

[zombezoo]

I remember reading that whole section in the instructions and deciding that I was ok. Shows how much I understood. Going back through posts to figure out what coil to get

 

[zombezoo]

Here's where I got the idea I could use this coil...

HEI Conversion Coil Question

 

[Don Frelier]

Here's where I got the idea I could use this coil...

HEI Conversion Coil Question

I'm sure it was well intentioned.
Perhaps he didn't read the instructions carefully enough.

 

[zombezoo]

Yeah, no judgement. It's just hard.to tell what will work. What am I looking for in a coil? Would prefer a stock style round unit since I already have a bracket. Looking to run 12v straight to the coil.

 

[Don Frelier]

A 3 ohm coil like the pertronix 40611 would be a safe bet.
But I'm not really an hei expert.

 

[Geoff 2]

The way I read the instructions, the F/thrower III coil should work with the HEI module. HEI has adaptive dwell AND current limiting [ internal ]. The MSD #8225 coil is the direct replacement in-cap coil for HEI & has a 0.31 ohm pri resistance, fractionally less than the III.
Plug gap should be 0.060" to get the best out of the system. Smaller gaps will not hurt anything.

 

[zombezoo]

I was surprised. I did read the documentation but not 100% understanding the different situations that coil could be used in, and not understanding how the hei module was similar or different from the pertronix components, I figured the ballast resistor was needed for other reasons than the coil. Thinking it through now that does seem wrong.
The one that failed was damaged in shipping, it had a clear dent in the corner, arrived outside it's factory box inside the larger shipping box and was clearly a bit beat up. It seemed to work ok so I thought it was ok.

Not sure what the real cause is, but I ordered the 40611 model and it arrives tomorrow. As I understand it, the fitech setup I have needed a non-ballast type.coil to use as a tach signal source which is what prompted them change. It was all working ok before it blew up so hopefully this new coil is the solution.

 

[493 Mike]

I am using this Ford coil (Rock Auto $ STANDARD MOTOR PRODUCTS FD478T (Economy) T-Series) and connector ( STANDARD MOTOR PRODUCTS HP4370 HandyPack; Gray) for my conversions with great results. Just using this HEI module (STANDARD MOTOR PRODUCTS LX301T (Economy) T-Series) and wiring as per my attached sketch.
Mike

 

[70bigblockdodge]

I get the HEI module part, way easier to get/replace on a road trip than a questionable Chrysler electronic box.
The insistence to get rid of the ballast resistor and dump 12 volts in a old style oil coil is just baffling, most times there is not even a misfire with the ballast resistor, why reinvent the wheel?
Get a coil from the parts store for a nineties GM TBI truck, Ford last distributor ignitions are 12volt coils not sure on years, pretty sure the iron plate surrounded coils from a 1990's Dodge truck is 12volt straight.
No, none of them are a can type coil, no they will not fit in your stock bracket. You have already modified your system so finish it with a modern coil, or leave the ballast resistor and carry a spare

 

[zombezoo]

FYI, received 3 ohm coil this morning and the instructions state this coil is not recommended for 8 cyl applications. Seems that I need the 1.5 ohm version. I'm going to return this one and purchase the 1.5 ohm

 

[RJ Squirrel]

That first coil does look like it was destined for failure. Have you checked the voltage at the coil while running high idle.
I believe our ignition guy Ray-Halifax shops recommends the Pertronix III coil for his HEI distributor mods.
I am using a 0.5 ohm E-coil with mine, I have burned up 4 modules in the last 1100 miles and still do not know why.
There are tons of HEI failure threads on the internet!
Good luck and report back with any success!

 

[zombezoo]

That first coil does look like it was destined for failure. Have you checked the voltage at the coil while running high idle.
I believe our ignition guy Ray-Halifax shops recommends the Pertronix III coil for his HEI distributor mods.
I am using a 0.5 ohm E-coil with mine, I have burned up 4 modules in the last 1100 miles and still do not know why.
There are tons of HEI failure threads on the internet!
Good luck and report back with any success!

Where do you have your module mounted?

 

[RJ Squirrel]

On a heat sink on the bottom of the distributor. Ground wire attached directly to the grounding mount screw.

 

[Armyvet25]

The HEI control modules are very reliable, but, remember, they were originally installed inside the Dist. As reliable as there are, THEY DO NOT LIKE HEAT.
I would mount on the firewall with a heat sink and a shield as far away from the engine as possible. coil was probably defective as well which contributed to the failure. Get a quality module not a local parts store chineezy one.

 

[zombezoo]

Canadian1968
Canadian1968

Has started making 3d printed hei module mounts that fit where the factory electronic module sat. I'm going to move mine there. I also had this failed module mounted on the base of the distributor.

I was using a Delphi DS10071 module, not sure of that qualifies as chineezy or not, it is made in China... I will see if I can source a gm factory one.

Some more photos of the damage to the coil (from shipping) I had seen dented coils before that worked for years so I didn't think much of it. Perhaps it was the root cause