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What did I do wrong here (HEI Conversion)

Pictures pictures want to see the carnage.
All the damage is inside the torque converter! Getting all the metal cleaned out.


IMG_1683.jpeg
 
@zombezoo the flamethrower lll coil is simply pulling to much current. The coil is just to hot for the standard HEI module. Your 1.5 ohm is pulling much less hence less heat. Although u are leaving some potential energy on the table..

Look up the primary resistance of an actual factory in cap coil. They are 0.5 - 0.7 ohms. Your trying to run 0.3 ohms . The module isn't going to like that.

I know u want to stick with canister style coil, so check out the petronix flamethrower ll rated ar 0.6 ohms.

The 1.5 you have running now will be fine but may struggle at high rpm. Look for something with just little less primary resistance , but also not to low!

The other option is a different module that can handle the extra current draw.
 
The HEI module has an internal current limiter, that limits current to 5.5 amps. A 1.5 ohm coil could draw 8 amps without current limiting. It is not the coil. As I said earlier, I think a bigger heat sink is needed. In the original HEI, the whole of the dist body is the heat sink.
 
The HEI module has an internal current limiter, that limits current to 5.5 amps. A 1.5 ohm coil could draw 8 amps without current limiting. It is not the coil. As I said earlier, I think a bigger heat sink is needed. In the original HEI, the whole of the dist body is the heat sink.
Exactly what is that? PURE SPECULATION OR BLIND SUPPOSITIONON YOUR PART. Show us the schematic of the HEI MODULE INTERNAL COMPONENTS...not how to connect it but the internal components and how they are connected...we'rewaiting......
BOBRENTON..
 
The HEI module has an internal current limiter, that limits current to 5.5 amps. A 1.5 ohm coil could draw 8 amps without current limiting. It is not the coil. As I said earlier, I think a bigger heat sink is needed. In the original HEI, the whole of the dist body is the heat sink.

Have to disagree. If what you say is true, then running the 1.5 ohm coil should running just as hot. If running the 1.5 ohm coil , nothing else changed is causing the module to run cooler. Then 100% the coil is having an effect, I'm not sure how you can argue that?

The petronix flamethrower 3 coil is actually designed for CD ignition system. I know I have only referenced the primary resisitance , but there are other parts of this coils design that do not match well with stock HEI module. I have also made this this mistake myself , trying to run a summit e-core coil with very similar characteristics , and I ran into the EXACT same problems of running to hot, then the car just randomly missing , backfiring, and finally dying.

As far as the stock HEI using the distributor as a heat sink , that is true. But that distributor is quickly heat soaked by the engine itself not exactly the greatest design . A stand alone HEI mounted on the fire wall or fender , with some sort of heat sink , not much larger than the module itself should provided much better heat dissipation. Especially being exposed to under hood air flow, as apposed to being trapped under the distributor cap , in the stock setup.
 
Have to disagree. If what you say is true, then running the 1.5 ohm coil should running just as hot. If running the 1.5 ohm coil , nothing else changed is causing the module to run cooler. Then 100% the coil is having an effect, I'm not sure how you can argue that?

The petronix flamethrower 3 coil is actually designed for CD ignition system. I know I have only referenced the primary resisitance , but there are other parts of this coils design that do not match well with stock HEI module. I have also made this this mistake myself , trying to run a summit e-core coil with very similar characteristics , and I ran into the EXACT same problems of running to hot, then the car just randomly missing , backfiring, and finally dying.

As far as the stock HEI using the distributor as a heat sink , that is true. But that distributor is quickly heat soaked by the engine itself not exactly the greatest design . A stand alone HEI mounted on the fire wall or fender , with some sort of heat sink , not much larger than the module itself should provided much better heat dissipation. Especially being exposed to under hood air flow, as apposed to being trapped under the distributor cap , in the stock setup.
A coil designed for a CD (Capacitive Discharge) system has totally different characteristics, as it's primary windings is energized with several 100 volts (from the ECU's internal components thru a switching SCR) for a rapid Discharge to the coil, producing the spark. As I've noted previously, the coil's inductive reactance and capacitive reactance factor into the coils performance and longevity. The person you reference takes many liberties with his analysies, many of which are unfounded or unsubstantiated.......just my opinion......
BOB RENTON
 
A coil designed for a CD (Capacitive Discharge) system has totally different characteristics, as it's primary windings is energized with several 100 volts (from the ECU's internal components thru a switching SCR) for a rapid Discharge to the coil, producing the spark. As I've noted previously, the coil's inductive reactance and capacitive reactance factor into the coils performance and longevity. The person you reference takes many liberties with his analysies, many of which are unfounded or unsubstantiated.......just my opinion......
BOB RENTON
Yes exactly, I know we have had our arguments in the past, but you are correct on this . The inductance of the flamethrower 3 coil, along with its turn ratio, low primary resistance . Are suited for the very rapid quick sparks that are characteristics of CD style ignitions. An inductive style ignition like the HEI looks for one big discharge per combustion . This is suited to a higher inductance. If your choosing the correct style, primary resistance and turn ratio, the inductance of the coil is generally going to be inline with your needs. Its kind of like the end result with all the parts put togetther. Basically when you go looking for a coil, the inductance isn't the main thing I look for.
 
@zombezoo the flamethrower lll coil is simply pulling to much current. The coil is just to hot for the standard HEI module. Your 1.5 ohm is pulling much less hence less heat. Although u are leaving some potential energy on the table..

Look up the primary resistance of an actual factory in cap coil. They are 0.5 - 0.7 ohms. Your trying to run 0.3 ohms . The module isn't going to like that.

I know u want to stick with canister style coil, so check out the petronix flamethrower ll rated ar 0.6 ohms.

The 1.5 you have running now will be fine but may struggle at high rpm. Look for something with just little less primary resistance , but also not to low!

The other option is a different module that can handle the extra current draw.
Bingo!

Picked up the 45011 flamethrower coil (0.6 ohm) and it's now running great.

Both the 0.3 and 1.5 coils had a rough idle that would smooth out once the rpms got over 1000, this thing now idles AND drives smooth. Drove around a bit and sat idling for about 20 min after, module temps are 140.

I still have a backfire on quick acceleration that I believe is timing curve related (I will start a separate thread), but I think this is the answer:
Use the GM module and this 45011 coil (if you want factory style coil).

Thanks for responding, I wasn't putting together that the 0.3 ohm coil was also outside the target range was also a problem. There's lots of conflicting info out there on this and it's hard to sort out what parts work with each other.
 
@zombezoo

SUCCESS! Great to hear its running well. You put in alot of work making sure all your wiring is in tip top shape , and finally got everything paired together ! Your right there is a ton of conflicting info out there. Or sometimes people may be using an aftermarket HEI unit instead of a factory replacement. I haven't read up on the specs of those , but I am sure they to would have their own coil to be paired with for best performance !

I'm curious as to what your Temps are like now.
 
Sorry didn't read your entire post.... 140f ... that's perfect!
After 30 miles of mixed driving, 80mph highway and stop and go street, I jumped out and grabbed a reading: 115 degrees.

Thing runs totally different.

So in summary:
GM/AC Delco Module: D1906 mounted on @Canadian1968 3d module with additional heat sink PN 10474610 modified to fit (see post #29)
Flamethrower 2 45011
Dedicated relay with feed from alternator side of the wiring harness, 14+ volts for both module and coil
NGK 2771 Plugs gapped to .45 (late rv.440 block requires 5/8 plugs)
Accel super stock 8 mm wires (cut to length)
 
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Just to confirm, that's my 3d mount with AC Delco heat sink added to it ? Giving those Temps?
 
Just to confirm, that's my 3d mount with AC Delco heat sink added to it ? Giving those Temps?
Been following this thread. Noticed you used all black wires, correct? Why not 4 different colors, less chance of wire in the wrong place. Great thread.
 
Been following this thread. Noticed you used all black wires, correct? Why not 4 different colors, less chance of wire in the wrong place. Great thread.

Well it actually came down to 2 things.

1. Was the cost , I didn't have 4 different colors of the same gauge when I built my first one.

2. After I made my first one , I really like the way it looked with them all being the same color ! Honestly thought it made look cleaner.

I actually had a choice between black or blue I had on hand . Went with black .

I did emboss the correct letters into the 3d print.. Under each hole is labeled the corresponding terminal it goes to.

Thanks for the interest!
 
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