HEI Conversion Coil Question

[RJRENTON]

Same subject, but different. How do you know if the HEI module is defective or damaged? 1- Either creates spark or it doesn't or 2- Develops a miss 3- Something else

The GM HEI module is inexpensive.....if in doubt, just replace it.....it's like a light bulb....it works or it doesn't......just my opinion......
BOB RENTON

 

[Canadian1968]

Same subject, but different. How do you know if the HEI module is defective or damaged? 1- Either creates spark or it doesn't or 2- Develops a miss 3- Something else

Like most diagnostic problems , eliminate variables. If everything else ( coil, wires, cap, distributor, voltage checks) checks out. Then only one thing left.

 

[1973dodger]

The GM HEI module is inexpensive.....if in doubt, just replace it.....it's like a light bulb....it works or it doesn't......just my opinion......
BOB RENTON

Do you have a brand preference? I think mine is an Eljin TP45 from NAPA.

 

[RJRENTON]

Do you have a brand preference? I think mine is an Eljin TP45 from NAPA.

NO PREFERENCE......I have an original Prestolite Dual point distributor in the '70 GTX, RS23V0A******, recurved to suit my specs, with out vacuum advance, with the original Mopar coil and balast resistor, cap, etc.....I prefer the original ignition system components. The engine runs just fine, to 6500 RPM....I do not race the car or have any intention of doing so.......
BOB RENTON

 

[Geoff 2]

E core coils are superior to canister coils. E core coils cost more than canister coils, yet they [ or a variant ] are used invariably in modern cars. There will be a good reason if a more expensive coil is used....such as able to run 060 or 080 plug gaps.
A canister coil is simply a ferrous bar with a N & S pole at each end. Some of the energy leaks into the atmosphere, lost forever, & NEVER converted into spark energy. They have high leakage inductance. The air gap for the magnetic field is the length of the bar. An E core coil has a very small air gap so less energy is lost to the surrounding air....& more energy is retained to produce spark energy.

 

[Kern Dog]

How about a recap for the S L O W members (Like me) that might consider something like this for my cars ? Was the wire diagram here:

....as simple as it seems? The HEI module just takes coil positive and coil negative as inputs?
Forgive my limited understanding here...I have always had trouble with electrical stuff. The input and output to the ballast resistor must go somewhere though, right? Where? The diagram at the bottom right shows two wires that intersect the coil positive. I can't make out the writing. Are those the RUN1 and RUN 2 wires ?

I have 3 big block vehicles here with factory type electronic ignition, one 360 with it and one 360 with points.
I've had numerous ECMs and ballast resistors crap out in one of the cars.
There have been pictures posted with a GM HEI module hidden in the back of a factory appearing ECM. I'd be inclined to go that route since it would look sort of like a factory job.
Skimming through this thread and others, I have gleaned that the ballast resistor is no longer needed nor wanted. Geoff suggests the use of one of those coils shaped like a cube. I'd want to package this as close to a factory installation as I could with the coil close to the distributor. I can make brackets.

 

[Gold Rush]

How about a recap for the S L O W members (Like me) that might consider something like this for my cars ? Was the wire diagram here:

View attachment 1745529
....as simple as it seems? The HEI module just takes coil positive and coil negative as inputs?
Forgive my limited understanding here...I have always had trouble with electrical stuff. The input and output to the ballast resistor must go somewhere though, right? Where? The diagram at the bottom right shows two wires that intersect the coil positive. I can't make out the writing. Are those the RUN1 and RUN 2 wires ?

I have 3 big block vehicles here with factory type electronic ignition, one 360 with it and one 360 with points.
I've had numerous ECMs and ballast resistors crap out in one of the cars.
There have been pictures posted with a GM HEI module hidden in the back of a factory appearing ECM. I'd be inclined to go that route since it would look sort of like a factory job.
Skimming through this thread and others, I have gleaned that the ballast resistor is no longer needed nor wanted. Geoff suggests the use of one of those coils shaped like a cube. I'd want to package this as close to a factory installation as I could with the coil close to the distributor. I can make brackets.

You are 100% correct thinking the two wires might be RUN 1 and 2. Since the ballast in not used the two voltages feed the ignition module and E-Core coil directly.

Remember back in the late 70s all the GM HEI distributors having ignition modules burning out frequently? Final cause was determined they were not getting ventilation inside the distributor so the just flat fried themselves. There are a number of brackets available facilitating external mounting for the HEI module (Google it) Here is what I used ( Mopar HEI Conversion ) Very well made and I've not had a single module fail.

 

[RJRENTON]

E core coils are superior to canister coils. E core coils cost more than canister coils, yet they [ or a variant ] are used invariably in modern cars. There will be a good reason if a more expensive coil is used....such as able to run 060 or 080 plug gaps.
A canister coil is simply a ferrous bar with a N & S pole at each end. Some of the energy leaks into the atmosphere, lost forever, & NEVER converted into spark energy. They have high leakage inductance. The air gap for the magnetic field is the length of the bar. An E core coil has a very small air gap so less energy is lost to the surrounding air....& more energy is retained to produce spark energy.

View attachment 1745519

In all regards, the core shown in the open core is, in fact, a laminated, hi silicone steel multi layer design. There is actually less core losses in the conventional design (core losses are the magnetic losses plus the copper losses [resistance of the wires used to generate the magnetic field] in the first place). Both designs are basically AUTOTRANSFORMER types.....no true magnetically coupling between the primary and secondary windings....the chief differences are physical arrangement.....both designs have possess but the flux losses shown in the e core center laminations are made to minimize the losses but permit the windings to be installed and welded to close the flux lines ......the secondary voltage is determined by the primary to secondary windings volts/turn ratio.......btw....I use to design utility transformers.....the operating principles are the same......
BOB RENTON

 

[RJ Squirrel]

In all regards, the core shown in the open core is, in fact, a laminated, hi silicone steel multi layer design. There is actually less core losses in the conventional design (core losses are the magnetic losses plus the copper losses [resistance of the wires used to generate the magnetic field] in the first place). Both designs are basically AUTOTRANSFORMER types.....no true magnetically coupling between the primary and secondary windings....the chief differences are physical arrangement.....both designs have possess but the flux losses shown in the e core center laminations are made to minimize the losses but permit the windings to be installed and welded to close the flux lines ......the secondary voltage is determined by the primary to secondary windings volts/turn ratio.......btw....I use to design utility transformers.....the operating principles are the same......
BOB RENTON

AHA so your one of the guys responsible for the transformers that convert single phase power lines into two phases, so us country boys out in rural America can have 240V in our shops- thanks!

 

[1973dodger]

NO PREFERENCE......I have an original Prestolite Dual point distributor in the '70 GTX, RS23V0A******, recurved to suit my specs, with out vacuum advance, with the original Mopar coil and balast resistor, cap, etc.....I prefer the original ignition system components. The engine runs just fine, to 6500 RPM....I do not race the car or have any intention of doing so.......
BOB RENTON

Bob, Thanks for your input in this thread. As far as different manufactures for the HEI modules, I have read in other forums that not all HEI modules are created equal, while others are just rebranded from the same manufacture. I do understand that proper heat sink is critical to the life of the module as much as anything. The reason I chose the Eljin module from NAPA was because of the lifetime warranty (as long as it was hooked up correctly of course)

 

[GTXDAN]

Kern this system is pretty simple. You can use it with a factory coil as long as you use a ballast resistor, or you use an "E" core coil like HEI uses without the ballast resistor. Here is the dizzy and coil I am going to run in my GTX.

This Speedmaster coil used to be sold by Summit for less than $30, but they don't sell them any more. You can use a normal looking coil without the ballast resistor as long as the primary resistance is less than .5 ohms. I left the wiring on my car along and just soldered a wire across the terminals of the ballast resistor to bypass it and run this "E" core.

This Pertronix coil will work without ballast resistor (primary resistance .320 ohms) and will look like stock. $60.45
PerTronix 44011 PerTronix Flame-Thrower III Ignition Coils | Summit Racing

Plus you can spend lots of money for a "high performance" HEI module, or just buy one that fits late 70s early 80s GM HEI dizzy for a little money. The truth of the matter is it justs fires the coil. It either works or not.

 

[GTXDAN]

Here's a Summit brand coil that you can run without the ballast resistor for only $31.79. Says it puts out 45,000v.
Summit Racing SUM-850496 Summit Racing™ High-Output Ignition Coils | Summit Racing

 

[RJRENTON]

AHA so your one of the guys responsible for the transformers that convert single phase power lines into two phases, so us country boys out in rural America can have 240V in our shops- thanks!

BTW......there is no two phase transformers. The common residential arrangement is single phase .....as 120/240 volt single phase or for light industrial 208Y/120 volt three phase or industrial it could be 480Y/277 volt three phase or 2400 volt three phase, derived by common delta to wye configurations or for Very light industrial applications an open delta primary/open delta secondary configurations (only 2 transformers required not the conventional 3 transformers)....It depends on the utility supplying the voltage and frequency (50 Hz Canada). In Tennessee, it's likely that you have 120/240 volt single phase power supplied by your utility....maybe the TVA......Just thought you might like to know......P.S.....I also designed industrial/plant electrical distribution systems to interface with the local utility....transformer sizing, short circuit current availability, circuit breakers, both oil, air and sulfur hexaflouride types.
BOB RENTON

 

[dadsbee]

(50 Hz Canada).

ya that'd work really well Bob seeing we trade power back and forth and our lines are all looped...

 

[1973dodger]

Kern this system is pretty simple. You can use it with a factory coil as long as you use a ballast resistor, or you use an "E" core coil like HEI uses without the ballast resistor. Here is the dizzy and coil I am going to run in my GTX.

View attachment 1745866View attachment 1745867

This Speedmaster coil used to be sold by Summit for less than $30, but they don't sell them any more. You can use a normal looking coil without the ballast resistor as long as the primary resistance is less than .5 ohms. I left the wiring on my car along and just soldered a wire across the terminals of the ballast resistor to bypass it and run this "E" core.

This Pertronix coil will work without ballast resistor (primary resistance .320 ohms) and will look like stock. $60.45
PerTronix 44011 PerTronix Flame-Thrower III Ignition Coils | Summit Racing

View attachment 1745868
Plus you can spend lots of money for a "high performance" HEI module, or just buy one that fits late 70s early 80s GM HEI dizzy for a little money. The truth of the matter is it justs fires the coil. It either works or not.

Good info Dan, I appreciate the way you explain things. It seems like several folks explain things over most of the common man's understanding.

 

[GTXDAN]

So in your case if you don't want the ballast resistor on the firewall just make a jumper wire to plug the 2 wires together and hook up your new coil (.5 ohms or less) as usual. Should work great.

 

[Geoff 2]

Crane cams was one of the few ign coil ign makers that published useful info about their coils.

Leakage inductance for their canister coils: 1.3 mH, 0.50 mH
Leakage inductance of their E core coils: 0.32mH, 0.14mH, 0.23mH

To imply or claim that a canister coil is more efficient than an E core coil is nonsense......

 

[Geoff 2]

Kern,
Looking at post #26, yes I believe you are correct: the two wires connecting to the coil [+] terminal are ign 1 & 2. I cannot see what else they could be.
Are you wanting to use a stock coil for originality? If so, a 0.5ohm bal res must be used. Either a single bal res from pre elec ign, 1971 & earlier....or the 0.5 ohm res that is half of the dual bal res. With this scenario: the ign 1 & 2 wires must connect to the 'B' terminal on the HEI module. You also connect one end of the bal res to this terminal. The other end of the bal res connects to the coil [+] terminal. This only applies to canister coil that require a bal res. An E core connects without the bal res.

 

[Kern Dog]

Kern,
Looking at post #26, yes I believe you are correct: the two wires connecting to the coil [+] terminal are ign 1 & 2. I cannot see what else they could be.
Are you wanting to use a stock coil for originality? If so, a 0.5ohm bal res must be used. Either a single bal res from pre elec ign, 1971 & earlier....or the 0.5 ohm res that is half of the dual bal res. With this scenario: the ign 1 & 2 wires must connect to the 'B' terminal on the HEI module. You also connect one end of the bal res to this terminal. The other end of the bal res connects to the coil [+] terminal. This only applies to canister coil that require a bal res. An E core connects without the bal res.

I'm not married to the idea of the stock style cannister coil.
Sometimes I'm stubborn to deviate from factory type stuff even when alternatives are better. It must be a comfort thing related to familiarity.
I liked the idea of an HEI module hidden behind the stock Mopar ECU case with the wiring all appearing factory-like. As far as the coil, I'm not picky about that...a cube type is fine.
In reality, I just want something reliable that works and IF I needed a replacement, I could find something fairly quick.
I've had troubles with my ignition randomly losing spark and barfing ECUs or ballast resistors. I don't like the bulk of those MSD systems. I have to have vacuum advance. In a perfect world, the MP electronic ignition conversion kit I put in way back in 2001 should be more reliable.
Here is the thing....I've cleaned the bulkhead terminals. I've changed every ignition part several times over the last 23 years and I still get the random no spark condition. The last time, both the ECU and ballast resistor crapped out. I'm just looking for reliability.

 

[Gold Rush]

I'm not married to the idea of the stock style cannister coil.
Sometimes I'm stubborn to deviate from factory type stuff even when alternatives are better. It must be a comfort thing related to familiarity.
I liked the idea of an HEI module hidden behind the stock Mopar ECU case with the wiring all appearing factory-like. As far as the coil, I'm not picky about that...a cube type is fine.
In reality, I just want something reliable that works and IF I needed a replacement, I could find something fairly quick.
I've had troubles with my ignition randomly losing spark and barfing ECUs or ballast resistors. I don't like the bulk of those MSD systems. I have to have vacuum advance. In a perfect world, the MP electronic ignition conversion kit I put in way back in 2001 should be more reliable.
Here is the thing....I've cleaned the bulkhead terminals. I've changed every ignition part several times over the last 23 years and I still get the random no spark condition. The last time, both the ECU and ballast resistor crapped out. I'm just looking for reliability.

It would be interesting to see how well the hidden GM style ignition module faired out mounted directly to the bulkhead. VERY important that the module has a generous amount of heatsink compound between it and the mounting surface. You might also cut out some of the stock ECU case sides and bottom providing air flow. That module needs to breath or it will fry itself just like it did back in the 1970s.

You would be surprised how HOT the E-Core spark is. I have an adjustable spark gap tester that I hooked into my system after the HEI upgrade. Got a BLUE-WHITE spark jumping over 3/8 of an inch.