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4-pin ignition module

Joined
Apr 29, 2001
Messages
2,141
Location
Rio Rancho, NM
Corvette
1981 HD Suspension; ZN1 Option
Everyone,

I need to know what is the polarity for the 4-pin module end that connects to the two wires in the distributor, so that I can connect the MSD harness for the 6AL.

Are the green wire (-) negative and the white wire (+) positive?

The L81 has a 7-pin, and I could not find info from Accel Ignitions.

Thanks!
 
GerryLP said:
Everyone,

I need to know what is the polarity for the 4-pin module end that connects to the two wires in the distributor, so that I can connect the MSD harness for the 6AL.

Are the green wire (-) negative and the white wire (+) positive?

The L81 has a 7-pin, and I could not find info from Accel Ignitions.

Thanks!
I've done a coupla 4-pin HEI-MSD 6 jobs ... without buying additional harness from MSD. On a 4-pin HEI ... the WHITE wire from PICKUP is POSITIVE magnetic and it connects to MSD's small VIOLET (+) "MAGNETIC Trigger" ... & the GREEN wire from PICKUP is NEGATIVE and it connects to MSD's small GREEN (-) "MAGNETIC Trigger" wire. On a 4-pin HEI you remove or bypass the module entirely ... and wire pickup directly to MSD.

I've never done 7-pin HEI-MSD 6 job ... but I can see from the diagram that it is wired QUITE different from 4-pin HEI-MSD 6 job.

If you'll go to www.msdignition.com you can download a free pdf ( MSD 6 Series Installation Instructions http://www.msdignition.com/pdf/6series.pdf ) that shows wiring diagram for 7-pin HEI (& many others too). I can see from the diagram that (when used with 7-pin) the MSD does not use its magnetic pickup wires (as with 4-pin) ... instead, 7-pin setup uses MSD's small RED (+) and small WHITE (-) "POINTS/AMPLIFIER TRIGGER" wires ... AND the 7-pin module STAYS PUT, is utilized and is connected. Looks like this can easily be done without buying additional harness from MSD. Download the pdf and you'll see just what to do ... on about page 17 of about 24 page pdf. Get it right the first time or you'll quickly smoke the MSD box ... and maybe the pickup / module too.
G'luck.
JACK:gap
 
Jack,

Thanks a bunch! I did call MSD, and even though the guy was trying to help me, he could not find the information.

So I went to my car, and checked, and I feel like such an idiot ::( ..I looked at the wires again with your guidance, and surely enough, the connector for the green wire IS different in size to the one with the white wire. The green connector for the MSD harness (P/N 8861) matches the one for the distributor as well as the violet-colored wire matches the connector for the white wire in the distributor.

I could explain my mistake by blaming it on the clogged sinuses, but I goofed. Thanks again for coming to my rescue.
 

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