Love it.
What did I do wrong here (HEI Conversion)
- Thread starter zombezoo
- Start date
Canadian1968
Well-Known Member
@zombezoo those wires really pop ! The wire looms that your using, what are those bolted to ? It doesn't look like valve cover bolts like other ones I have seen.
@RJ Squirrel that is a serious heat sink you got there ! I don't think you should be worried about that moduel holding any excessive heat ! In the one picture it looks like your coil is almost sitting on the valve cover ?
@RJ Squirrel that is a serious heat sink you got there ! I don't think you should be worried about that moduel holding any excessive heat ! In the one picture it looks like your coil is almost sitting on the valve cover ?
Had to come up with a solution... They are R&M Billet Wire Looms (1104-K), They did not come with hardware to mount to the valve cover, I purchased some Jeep valve cover studs (6035968AA) and trimmed them down to fit the heads hoping I could mount the frames to the stud, Turned out that would not fit against the base of the valve cover on the passenger side and the Tri-Y headers on the drivers side rise up above the base of the valve cover so they would hit there too.
I ended up getting some 1/4 20 threaded couplings and some jam nuts to raise the whole setup up and some 1/4 20 allen bolts to hold them down. Came out pretty good. It just clears the drivers side primary pipe and keeps everything pretty well locked in place so they don't move around and hit the header.
The plot thickens...
Received the 44011 0.32 ohm coil and installed it today. Within 5 minutes of driving I notice it's breaking up under load. I pull over and check how how the coil is by hand, cool to the touch. I touch the front of the hei module, warm, I touch the heat sink and nearly burn my hand. I head back home and grab my ir thermometer and read almost 150 degrees on the heat sink (car was still idling).
I let it cool down while I swap back to the 1.5 ohm coil. At idle 98 degrees (about 48 degrees today). Went for a drive and heat sink did not get over 100 degrees. I believe the short run with the low ohm coil may have already damaged the hei unit, it does not feel like it runs as strong as it did. I'm going to swap to my spare to confirm.
Received the 44011 0.32 ohm coil and installed it today. Within 5 minutes of driving I notice it's breaking up under load. I pull over and check how how the coil is by hand, cool to the touch. I touch the front of the hei module, warm, I touch the heat sink and nearly burn my hand. I head back home and grab my ir thermometer and read almost 150 degrees on the heat sink (car was still idling).
I let it cool down while I swap back to the 1.5 ohm coil. At idle 98 degrees (about 48 degrees today). Went for a drive and heat sink did not get over 100 degrees. I believe the short run with the low ohm coil may have already damaged the hei unit, it does not feel like it runs as strong as it did. I'm going to swap to my spare to confirm.
Canadian1968
Well-Known Member
You are grouding the module correct ?
yes. dedicated ground that goes back to the coil bracket on the block.
I have some other things to chase down before I attempt anything else here. I just realized that I have not confirmed voltage at the coil even though I know the bulkhead wiring is suspect on this vehicle. Battery voltage (at the battery) is only 12.7 when running suggesting I have some voltage drop across that bulkhead connector.
I'm going to stop here and deal with my other known issues first:
- Fresh plugs gapped to .45
- Replace engine and under dash wiring harnesses with new units
- Dedicated fuse/relay block for aftermarket power loads fed from the alternator battery post. (I plan to start a separate thread about that to vet my thoughts on this). I have the following aftermarket items: EFI, Fuel Pump, HEI Module.
I just got back from a 120 mile cruise, car ran great. The heat sink and the module were 139 degrees, won't get any cooler than that unless it is moved out of the engine bay. I believe operating temps of 200 degrees is normal for them.
Another thing that kills the modules is leaving the ignition on (powering up the module) without starting the car.
Another thing that kills the modules is leaving the ignition on (powering up the module) without starting the car.
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Thats helpful to know, thanks. I have too many variables here, going to work on eliminating some of the other know problems and come back to this. Thanks again to all!
Canadian1968
Well-Known Member
Well 12.7 is definitely a problem. You should be at least 13.6 range.
I know you said your going to start another thread about it. But have you upgraded your alternator , to handle all the new toys? You can also check what kind of volts your getting for power feed to the HEI.
I know you said your going to start another thread about it. But have you upgraded your alternator , to handle all the new toys? You can also check what kind of volts your getting for power feed to the HEI.
I added to the sticky on the subject 72RoadrunnerGTX already responded.
I did upgrade the alternator but the problem is really in the harness. My vehicle is a former parts car and it donated its good harness to another vehicle and inherited a hacked up one. The bulkhead connector was bad 25 years ago and im sure its worse now. With what I have learned from his videos, I can see the upgraded alternator may have just made the situation worse.
I have a stack of things I want to do to this car this year, pulling the dash to refurbish it (dash pad, paint, wiring etc) was not in the plan till later this year. I'm realizing I can probably repair the bad connections in the bulkhead by removing the failed connection and patching with a short bit of wire and some powerwerx connectors which should carry current better. If the weather cooperates, thats this weeks/this weekend's plan. As I do that project, I will confirm voltages at the coil and alternator and make sure I address any voltage drop.
Geoff 2
Well-Known Member
At 0.32 ohms on the primary winding, that is about half of what the OEM HEI coil was, 0.6 ohm.
The HEI modules had internal current limiting to about 5.5 amps, so I suspect the module is faulty.
The HEI modules had internal current limiting to about 5.5 amps, so I suspect the module is faulty.
Canadian1968
Well-Known Member
Found this very interesting page/ article its a bit of long read but explains some of the problems u and others may be having !
I'm trying to post the link but it's not letting me... but this is the part that caught my eye.
Using a lower-resistance coil can activate the current-limiter, which may solve the problem, but care should be taken. Whenever the current-limiter is activated, there is a potential for a lot of heat to generate inside the HEI module. If the dwell is extended by the reluctor design, as in the Kawasaki, there is the possibility of extended periods of current-limiter activation. The HEI module may destruct.
I'm trying to post the link but it's not letting me... but this is the part that caught my eye.
Using a lower-resistance coil can activate the current-limiter, which may solve the problem, but care should be taken. Whenever the current-limiter is activated, there is a potential for a lot of heat to generate inside the HEI module. If the dwell is extended by the reluctor design, as in the Kawasaki, there is the possibility of extended periods of current-limiter activation. The HEI module may destruct.
Canadian1968
Well-Known Member
It seems to be related to modifying motorcycles with the use of an HEI module , but some info that I have never read before .
General Motors HEI Ignition Modules
http://gpzweb.s3-website-us-east-1.amazonaws.com/Ignition/HeiModules/Hei4pinDR100moduleNotes.txt
General Motors HEI Ignition Modules
http://gpzweb.s3-website-us-east-1.amazonaws.com/Ignition/HeiModules/Hei4pinDR100moduleNotes.txt
myfeather626
Well-Known Member
That happened to me in my Flat Bottom boat at Lake Elsinore. I have a Hemi motor in it with direct drive set up I got water spray up on the engine that was one cold event g before getting towed back to the Loading Ramp!
Just as an update to any who were involved in this:
1) I completed my engine and under dash harness replacement as well as the modifications to run all my aftermarket electrical loads on the alternator side of the electrical system on a dedicated set of wiring. I now have 14.3V at the coil and HEI Module (VS 12.7)
2) I have the HEI and coil on a dedicated relay fed fused circuit separate.
3) My odd "ignition" issues seem to be timing rather than the ignition system itself. For whatever reason, this motorhome 440 wants LOTS of timing at idle, I ended up backing the base timing down to 6 and connecting the vacuum advance to manifold vacuum to give all the advance at idle. Its not perfect but its working for now. Im rebuilding another block and will address this further with the new engine.
4) Fresh plugs gapped to .45. The ones that were in were pretty dirty. The short time I ran the thermoquad on the car left them pretty carboned up.
5) I reverted back to the 40111 Coil (1.5 Ohm) due to the HEI module running cooler with it. The 44011 (.32 Ohm) coil would cause the HEI module to run almost 200 degrees after a short time driving around in 50 degree weather. The 1.5 Ohm coil runs the module around 120 degrees I don't know if this is expected or not as this is the only car I have to compare but the heat concerned me more than the coil ohm rating being outside of the recommended spec.
That said, the car is running well enough for now, thanks for all who helped.
1) I completed my engine and under dash harness replacement as well as the modifications to run all my aftermarket electrical loads on the alternator side of the electrical system on a dedicated set of wiring. I now have 14.3V at the coil and HEI Module (VS 12.7)
2) I have the HEI and coil on a dedicated relay fed fused circuit separate.
3) My odd "ignition" issues seem to be timing rather than the ignition system itself. For whatever reason, this motorhome 440 wants LOTS of timing at idle, I ended up backing the base timing down to 6 and connecting the vacuum advance to manifold vacuum to give all the advance at idle. Its not perfect but its working for now. Im rebuilding another block and will address this further with the new engine.
4) Fresh plugs gapped to .45. The ones that were in were pretty dirty. The short time I ran the thermoquad on the car left them pretty carboned up.
5) I reverted back to the 40111 Coil (1.5 Ohm) due to the HEI module running cooler with it. The 44011 (.32 Ohm) coil would cause the HEI module to run almost 200 degrees after a short time driving around in 50 degree weather. The 1.5 Ohm coil runs the module around 120 degrees I don't know if this is expected or not as this is the only car I have to compare but the heat concerned me more than the coil ohm rating being outside of the recommended spec.
That said, the car is running well enough for now, thanks for all who helped.
Geoff 2
Well-Known Member
It wants lots of idle timing? Why doesn't that surprise me...
Being motor home, it is probably a low comp engine....& they need more timing.
Bad move going to the higher resistance coil. If the module is getting hot, use a larger heat sink.
Being motor home, it is probably a low comp engine....& they need more timing.
Bad move going to the higher resistance coil. If the module is getting hot, use a larger heat sink.
Mine made it happily past the 200 miles mark- my problem was the bone headed move leaving 1-3-5 wires behind the PS pump zip tied together- dumb I know but I am confessing to add to the "dont do this" list.
Then my torque converter blew up- now the trans is in pieces on my table.
Then my torque converter blew up- now the trans is in pieces on my table.
Considered that but wanted to spend some time figuring out why it was getting so hot with the recommended ohm coil and why not with one thats not recommended. (and further more, is 200 degrees even a problem??)
Short on time the next few weeks so I opted for: less hot = more better
I will report back if I end up regretting that decision. I'm driving around with the other coil and a spare HEI module and some tools so worst case it gets swapped where it dies.
Pictures pictures want to see the carnage.
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