What is this wire

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Fittrjoe

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Hey everyone
My 67 Barracuda has a large wire almost 1/4” dia going from the alternator post to the Starter Relay ( #8 ?) I’ve traced it out and for sure it is NOT fused or fusible link.
I’m sure this wire was added when the Ammeter bypass WAS done by the previous owner during the Restomod process just prior to me buying the car 3 years ago.
I just did the Crackedback headlight harness upgrade which was a huge success ( MUCH brighter headlights and safer for wiring) and am trying to sort out other potential problems
Question 1:should this wire be fused and if so HOW do I do it? It’s the Big RED wire on the right in both photos
Question 2: What is the purpose of this wire?
Thanks in advance
Joe

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That's PART OF the ammeter bypass. It bypasses "everything" on "the other side" of the firewall connector and puts the alternator output DIRECTLY to the battery. Yes, IMO, it should be fused. I believe it needs to be at least what the maximum output of the alternator is. Possibly more. More experienced minds will be able to advise better on fuse size. I don't think I'd use fusible link, though. Maybe a maxi fuse.
 
I made the same ammeter bypass modification some months ago.
This big wire charges the battery and feeds the whole car wirings. Normally it has to be protected by a standard fuse or a 14 Ga. fusible link.

AMP bypass eng.jpg
 
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Fuse and inline holder/fuse block rated for just above ALT max amps or fusible link wire (3 sizes smaller than the correct wire gauge for circuit under continuous load and not in a bundle with other wiring. Link should be about six inches long, no more than 9, and not bundled with other wiring): McMaster-Carr

Direct solder or if your skills soldering are not excellent, reducing butt splice and heavy gauge heat shrink or good tape: McMaster-Carr

This traditional cotton tape holds better than common plastic tapes (also at hardware stores): McMaster-Carr
 
Put the fusible link near the battery end. If there's an accident and the wire gets grounded, the fuse blows instead of things getting all arcweldy.
 
Thanks so much guys
So either Maxi fuse rated at Alternator amps ( 65 in my case ) or a fusible link in line near Battery away from other wiring.
I’m leaning toward Maxi fuse
Anyone know where I can get one or have pics of an install?
Really appreciate all the advice guys !
 
You need a wire to handle max output of the alternator, and a fuse small enough to protect that wire
 
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