wiring question/alternator up grade
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Joined: Apr 2015
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From: Warrington PA
wiring question/alternator up grade
Im thinking of upgrading from the stock 10SI/ 63 amp to a 100amp just for the little extra power at idle and because I have to get a new alternator anyway. I have read dozens of posts on doing an upgrade but Im confused about a couple things.
If I went to a 100 amp I would run a new larger line (6 or 8ga) from the alt BAT post to the starter BAT post and put a fuse block or fusible link on it for protection, that being said I would remove the stock red wire that went from the BAT post to the junction block (post) on the drivers side fender well, correct and is that the only wire I need to delete from the old harness?
and secondly, if I run a larger wire to the starter BAT post from the new larger alternator wouldn't that also be feeding the main power to my wiring harness thats off that same BAT post on the starter, how is that portion of the harness protected from the higher amps?
If I went to a 100 amp I would run a new larger line (6 or 8ga) from the alt BAT post to the starter BAT post and put a fuse block or fusible link on it for protection, that being said I would remove the stock red wire that went from the BAT post to the junction block (post) on the drivers side fender well, correct and is that the only wire I need to delete from the old harness?
and secondly, if I run a larger wire to the starter BAT post from the new larger alternator wouldn't that also be feeding the main power to my wiring harness thats off that same BAT post on the starter, how is that portion of the harness protected from the higher amps?
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Precisely. New large wire from Alternator to battery terminal on starter solenoid. Old red wire that went to large post of Alternator can be deleted.
None worries about putting to much current through the rest of your car.
I run a 140amp Tuff Stuff Alternator. Works great. I have electric fans and EFI with constantly running fuel pump.
None worries about putting to much current through the rest of your car.
I run a 140amp Tuff Stuff Alternator. Works great. I have electric fans and EFI with constantly running fuel pump.
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From: Virginia
Your plan sounds good. On @Richard454's recommendation, I picked up some MBRF fuses and holders. See if those work for your starter fuse solution. He has posted some helpful wiring diagrams in other threads.
In later years, the starter extension harness was separately replaceable and contained fusible links. In 74, it may have been single wire with a fusible link, but still fed from the battery terminal on the starter. In any case, you aren't changing how the car gets power, since it was all pulled from the starter anyway.
In later years, the starter extension harness was separately replaceable and contained fusible links. In 74, it may have been single wire with a fusible link, but still fed from the battery terminal on the starter. In any case, you aren't changing how the car gets power, since it was all pulled from the starter anyway.
