Ok recently with help from a few Datsun friends I now have my electronic dist. & HEI module hooked up & the 620 is running great now. My truck is a 74 & has a Z 18 motor which originally came with points. I thought it would be good to post pics of the wiring & the writeup a friend sent me. Without my friends help it wouldnt have gotten done so soon so a big thanks to those guys. The dist. came out of a 76 610 w/ L 20 motor....
Electronic ignition using HEI module. pics +writeup
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Pac. coast Datsun
- Posts: 286
- Joined: Wed Dec 31, 1969 5:00 pm
-
Pac. coast Datsun
- Posts: 286
- Joined: Wed Dec 31, 1969 5:00 pm
-
Pac. coast Datsun
- Posts: 286
- Joined: Wed Dec 31, 1969 5:00 pm
this is the HEI i went with...
http://www.partsamerica.com/ProductD...pe=194&ptset=A
I plan on moving the HEI & using a small piece of alluminum under it to act as a "heat sink". The HEI's tend to get hot & that's not good for them.Also make sure the HEI is grounded or it will malfunction.
A BIG thanks to Mklotz for providing the writeup & help along the way.
> Wiring for the HEI unit.
>
> W - Connects to the positive lead at the distributor.
> G - Connects to the negative lead at the distributor.
> C - Connects to the negative side of the coil.
> B - Connects to the positive side of the coil.
>
>
> Okay...I'll add this to it........
>
> You will need a new wire from the RED wire on the dist to the W on the HEI
> unit.
> You will need a new wire from the GREEN wire on the dist to the G on the
> HEI unit
> These two wires are what "senses" the tiny voltage spike that will be sent
> from the pickup in the dist.
>
> You will need a new wire from the (+) of the coil to the B on the HEI
> unit. This provides the power to the HEI unit. It's electronics needs to
> get power from somewhere. You will "add" this wire to the existing wires
> on that terminal of the coil. You will have wires on there from the
> ballast resistor, the "start/crank"(full 12v) wire from the ign switch. Do
> not remove the ballast resistor unless you have a coil that is rated for a
> constant 12v. If you remove the ballast, you can simply connect the two
> wires from the resistor together. You may have only one wire at each end
> of the resistor and then you have a 2nd wire on the (+) term of the coil.
> The second wire is the "start/crank" wire from the ign switch. You should
> be able to see which wire runs from the resistor to the coil. If not, the
> black/white is from the resistor and the red is from the ign sw. If you
> simply take the resistor out without connecting to the two wires together,
> your engine will only fire when the key is in the crank position and will
> die when you quit cranking. If you remove the "start/crank" wire, you
> will still get volts to the coil through the resistor in the crank
> position(I double checked that on the '74 620 w/man trans wiring), but the
> starter pulls a lot of amps and you may not get enough power to the coil
> to get a good enough spark to start the eng.
>
> The wire from the (-) term of the coil can be the old one running to the
> dist, but I'd just run new and disconnect the old one. You may have two
> wires on that term...one will be the tach if you have one. This wire runs
> to the C on the HEI unit and turns the coil on and off like the points
> did.
>
> The HEI unit grounds itself through the metal plate on it's backside and
> the collets in the mounting screw holes. You want to make sure you mount
> the unit to a piece of aluminum with a small amount of heat sink compound
> for heat transfer. Then mount the alum bracket to a good chassis ground.
> I would try to tuck it up, more out of the way so that water and debris
> flying up don't hit it. It was designed to be inside the GM distributor.
http://www.partsamerica.com/ProductD...pe=194&ptset=A
I plan on moving the HEI & using a small piece of alluminum under it to act as a "heat sink". The HEI's tend to get hot & that's not good for them.Also make sure the HEI is grounded or it will malfunction.
A BIG thanks to Mklotz for providing the writeup & help along the way.
> Wiring for the HEI unit.
>
> W - Connects to the positive lead at the distributor.
> G - Connects to the negative lead at the distributor.
> C - Connects to the negative side of the coil.
> B - Connects to the positive side of the coil.
>
>
> Okay...I'll add this to it........
>
> You will need a new wire from the RED wire on the dist to the W on the HEI
> unit.
> You will need a new wire from the GREEN wire on the dist to the G on the
> HEI unit
> These two wires are what "senses" the tiny voltage spike that will be sent
> from the pickup in the dist.
>
> You will need a new wire from the (+) of the coil to the B on the HEI
> unit. This provides the power to the HEI unit. It's electronics needs to
> get power from somewhere. You will "add" this wire to the existing wires
> on that terminal of the coil. You will have wires on there from the
> ballast resistor, the "start/crank"(full 12v) wire from the ign switch. Do
> not remove the ballast resistor unless you have a coil that is rated for a
> constant 12v. If you remove the ballast, you can simply connect the two
> wires from the resistor together. You may have only one wire at each end
> of the resistor and then you have a 2nd wire on the (+) term of the coil.
> The second wire is the "start/crank" wire from the ign switch. You should
> be able to see which wire runs from the resistor to the coil. If not, the
> black/white is from the resistor and the red is from the ign sw. If you
> simply take the resistor out without connecting to the two wires together,
> your engine will only fire when the key is in the crank position and will
> die when you quit cranking. If you remove the "start/crank" wire, you
> will still get volts to the coil through the resistor in the crank
> position(I double checked that on the '74 620 w/man trans wiring), but the
> starter pulls a lot of amps and you may not get enough power to the coil
> to get a good enough spark to start the eng.
>
> The wire from the (-) term of the coil can be the old one running to the
> dist, but I'd just run new and disconnect the old one. You may have two
> wires on that term...one will be the tach if you have one. This wire runs
> to the C on the HEI unit and turns the coil on and off like the points
> did.
>
> The HEI unit grounds itself through the metal plate on it's backside and
> the collets in the mounting screw holes. You want to make sure you mount
> the unit to a piece of aluminum with a small amount of heat sink compound
> for heat transfer. Then mount the alum bracket to a good chassis ground.
> I would try to tuck it up, more out of the way so that water and debris
> flying up don't hit it. It was designed to be inside the GM distributor.