Engine wiring help please!!
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Joined: Oct 2015
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Engine wiring help please!!
I’m working on a restoration of a 68 Vert I purchased last year. At some point in the past the car was rewired with a painless harness, but it was really hacked up so I decided to rewire from front to back. I purchased lectric limited harnesses. I have installed the rear, forward, and dash harness but I am running into a problem wiring the engine wiring. It has a zz427 engine with an MSD 6AL ignition, HEI distributer, and the tach has been converted to electric as well. I have read the instructions for the MSD, but I am unsure of how to wire everything together. I want to avoid cutting the engine harness if at all possible. Can anybody tell me in detail how to wire these?
I am a novice with limited abilities, so any details are greatly appreciated!!
I am a novice with limited abilities, so any details are greatly appreciated!!
Is my vette stock?? HAHA
Joined: Oct 2015
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you shouldnt have to cut anything. you'll have to seal up the coil wires that are in your harness. You'll have to add a wire from your fuse block from the extra ignition plug to the hei.
the tach can be powered from the hei or the MSD.
'i dont have a 6AL yet but the power for that can come from the fuse block or the batt connection on the starter, which ever the directions specify.
You're wire size will be specified by MSD.
the tach can be powered from the hei or the MSD.
'i dont have a 6AL yet but the power for that can come from the fuse block or the batt connection on the starter, which ever the directions specify.
You're wire size will be specified by MSD.
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you shouldnt have to cut anything. you'll have to seal up the coil wires that are in your harness. You'll have to add a wire from your fuse block from the extra ignition plug to the hei.
the tach can be powered from the hei or the MSD.
'i dont have a 6AL yet but the power for that can come from the fuse block or the batt connection on the starter, which ever the directions specify.
You're wire size will be specified by MSD.
the tach can be powered from the hei or the MSD.
'i dont have a 6AL yet but the power for that can come from the fuse block or the batt connection on the starter, which ever the directions specify.
You're wire size will be specified by MSD.
From the MSD instructions there are a couple heavy gauge wires that go directly to the battery, a 12v switched source that will wire to the fuse panel, magnetic pickup connectors that connect to the distributor. There are also a positive and negative coil wire that need to be connected to the distributor.
Does the distributor get is power from the MSD box? It is grounded to the intake now, but I do not see a wire to a power source.
The back of the tach has a connector spot for a ground, 12v switched source, and signal wire. Where does the tach get its reading from?
Could I wire the MSD box and Tack power source to the same switched power source?
Racer
Joined: Jul 2015
Posts: 396
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From: Lehigh Valley Pennsylvania
From the MSD instructions there are a couple heavy gauge wires that go directly to the battery, a 12v switched source that will wire to the fuse panel, magnetic pickup connectors that connect to the distributor. There are also a positive and negative coil wire that need to be connected to the distributor.
Does the distributor get is power from the MSD box? It is grounded to the intake now, but I do not see a wire to a power source.
The back of the tach has a connector spot for a ground, 12v switched source, and signal wire. Where does the tach get its reading from?
Could I wire the MSD box and Tack power source to the same switched power source?
Does the distributor get is power from the MSD box? It is grounded to the intake now, but I do not see a wire to a power source.
The back of the tach has a connector spot for a ground, 12v switched source, and signal wire. Where does the tach get its reading from?
Could I wire the MSD box and Tack power source to the same switched power source?
I used the MSD distributor, which is a 2 wire plug. An old points distributor switches ground only so a single ground wire coming from the distributor is all you will see. I would have to look at the wiring diagram to see where this connectds to the 6AL box. However, you state that you have a HEI. There appears to be several different HEI configurations. We would need a picture to see what you have.
I used the old coil positive as the switched source to activate the 6AL box. It would have been abandoned with the 6AL setup.
There is a tach output signal on my 6AL box but I don't use it. I assume this would go to your tach. There is an ignition keyed source
at the fuse panel at the pedals. Grounds are everywhere.
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If the rest of the wiring connectors look anything like the picture you posted, you have no choice but to re wire the entire car or risk a fiberglass blob
Melting Slicks
Joined: Apr 2001
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From: Olmsted Falls, Ohio
You can almost tell what happend with this old thread.
poster 449er was probably replying to the "related thread" and hit "end" and the "end" was this thread.
I wish the RELEATED THREAD thing was gone. I have gone to the bottom of quite a few threads and posted on the wrong thread then had to delete. ANNOYING!
poster 449er was probably replying to the "related thread" and hit "end" and the "end" was this thread.
I wish the RELEATED THREAD thing was gone. I have gone to the bottom of quite a few threads and posted on the wrong thread then had to delete. ANNOYING!
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