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Discussion Starter · #1 ·
Since we're on the subject of alternator upgrades, how many amps can the original wiring handle? There are "bolt-on" upgrades of 80, 100, 105, I think I even saw a 140 amp. Assuming the original harness is in good shape, and we're not doing 1-wire conversions, when should we worry? Mine is a 71, would the year of the car make much difference?
 

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The factory #10 wire is good for about 40 A continuous to the horn relay, 30 A to the fuse block. Up grade to a #8, alt to horn relay, should be good for 60 A continuous to the horn relay 40 A at the fuse black. Up grade to #6. Alt to the horn relay, should be good for 80 A continuous to the horn relay, again 40 A at the fuse block. All can handle higher for short periods. I'm sure that others will give lower ratings.
 

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Discussion Starter · #3 ·
Ok, so I'm electrical knowledge challenged. If I'm installing a 105 amp alternator, I should upgrade to at least #6 from alt to relay? Should I also upgrade to #6 to fuse block? Should I go bigger?

Thanks
 

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Cecil
What are you trying to add and where? Upping the line to the fuse block isn't going to help much because all the wires coming out of the block are still the same size. Besides that you won't be able to fit the larger wire in the bulkhead connector pin.
 

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Discussion Starter · #5 ·
I only want to add whatever I need. I'm getting a 105A alternator that uses the existing wiring (not 1-wire). Just want to know what I need to do to keep things from melting...
 

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Well, these future items may need their own wire and fuse run from the battery, junction block, or horn relay.
 

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cecil
the alternator will only put out what your accessories/battery need to operate. If you never add electric fans, high amp stereo, etc, etc your 105 Amp alternator will never produce that much and your current wiring (in good shape) is adequate. If you add stuff you will need to change wire to the relay. Clear as mud I bet
 

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Discussion Starter · #8 ·
Clear now! I thought the alt. put out whatever it was going to put out, and the regulator took care of it.

Thanks for the info. New alt. is supposed to be here tomorrow...
 

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If you have an AMP meter (ammeter) in your car that someone added,....and IF your battery ever goes dead or is very dishcharged......

That alternator will send UP TO the full 105 amps through the wire to and from the ammeter.

Also, check to make sure the wiring insulation still looks good and is not brittle, cracked, or missing. Make sure the wires at the connectors & terminals look good.
 

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Discussion Starter · #10 ·
Ok, I put the new alternator in this morning. I remember some posts about making sure the mounting points are clean so it gets a good ground. There's a ground terminal on the back, would it be sufficient to wire that terminal to the radiator support?
 

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The alternator mount, if clean and tight, is all that is needed. Also the main ground cable or negative battery cable is attached to the top alternator bracket. Make sure the cable attaching point has good clean metal to metal contact and make sure that the bracket makes good clean contact with the engine block.
 
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