HEI conversion question

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Kendog 170

Kendog 170

Let the boy go !
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Has or is anyone running this particular conversion on their ride ? I have a MSD set up now but also am wiring the factory 1974 Ignition module in as a back up as I got stranded once when the MSD fail. I figured if I did this setup I won't need to wire in a Ballast Resistor . If anyone has a bad box they want to donate for my cause let me know. I already ordered a Module.

ECU conversion.jpg
 
I am not running that exact set up, but I am running an HEI module on my 440. Clean set up and no ballasts and can get parts at any parts store.
 
Do either of you have a wiring diagram for this setup? I have HEI on a truck I bought (non-running) and it's not clear where the wires are supposed to go.
 
Several of us run that HEI module. The only problem is being able to quickly substitute it for the MSD as the MSD wiring is quite different. Here is a simplified diagram one of the guys here made

Be aware you cannot simply "hang the box" in there. The HEI MOUNTING must be grounded (as well as some heat sink)

Both MSD and this system you bypass the ballast

4pin-jpg-jpg.jpg
 
@67Dart273, Many thanks - this is what I needed. I do not have any MSD on the truck.

Is there any polarity going to the distributor? That's the mystery on the truck. The I have two loose wires for the distributor (no factory connector) but the distributor is gone. I'm guessing since the distributor is basically a switch, it shouldn't make any difference but I thought I'd double check before repairing and re-installing the wiring.
 
The pick up produces a tiny ac signal so polarity is a issue. The HEI just amplifies it to turn the coil on and off to keep it simple.
 
your polarity will become obvious as the timing will have changed. But the same reluctor (some dual keyed and flipped over) and pickup were used on a CW LA and a CCW RB. IDK if Mopar changed the connector to make it opposite between the LA and the B/RB.
 
67Dart273 said:
Be aware you cannot simply "hang the box" in there. The HEI MOUNTING must be grounded (as well as some heat sink)
Click to expand...

Noted.
In the pic there is aluminum for mounting and for heat sink, I'm thinking some paste in between . Pic also shows a ground. Just need to figure way to attach alum. to box. Maybe a stud welder to box then mount alum.
ecu-conversion-jpg.jpg
 
Definitely need the heat soak paste regardless how it is mounted or to what.
 
halfafish said:
@67Dart273, Many thanks - this is what I needed. I do not have any MSD on the truck.

Is there any polarity going to the distributor? That's the mystery on the truck. The I have two loose wires for the distributor (no factory connector) but the distributor is gone. I'm guessing since the distributor is basically a switch, it shouldn't make any difference but I thought I'd double check before repairing and re-installing the wiring.
Click to expand...
"Polarity" does make a difference because the trigger is (example) first a positive spike and then negative spike. "Let's say" the box is triggered by the positive. This means that if you reverse the wires, the trigger point in time/ rotation is MOVED and the rotor will not be pointing 'where the spark is' happening. Google "rotor phasing."

Look at the diagram posted, the color of the PICKUP wires (distributor) Those colors are normally correct as shown. The remaining wires to the HEI are not relevant as to color
 
That box mount is just to keep the stock look. Not important for me since my 1965 Dart had points. I used the later 8-pin HEI module w/ GM coil, which is much easier wiring since a GM cable connects the two and it uses quality sealed connectors (Metripak). TrailBeast here sells it kitted, otherwise take from a junkyard 85-95 GM pickup. To insure pickup polarity, wire temp w/ wire nuts and spin the distributor by hand, with the coil HV lead going to a test spark plug (or the end held near an engine ground). Clamp a timing lamp over the HV lead and shine at the distributor reluctor teeth. If the teeth align with the pickup (when sparking), you have the polarity correct. If the pickup is in-between reluctor teeth, you have the pickup wires reversed. The later will still spark, but will be erratic in time.
 
Your coil will determine whether you need a ballast resistor, NOT the HEI module.

If your coil is designed to use a ballast resistor, it will run hot & probably burn out if you omit/bypass the resistor.

If you want the 'best bang for the buck' with the HEI module, use a modern E core coil such as the MSD #8207 [ no b/resistor needed ].
 
I already have a Blaster 2 coil. This would only be a back up if my MSD failed again.
 
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