upgrading alt wiring

I want to upgrade my alternator wire with thicker gauge but instead of simply removing the factory and replacing it with the new wire, I want to keep the factory wire there and also run the new wire. I cant trace the factory wire because its very hard to see and also the wire runs through tons of different size wire looms. The only thing I can see if where the wire runs to the alternator and where it connects to the battery. Could I simply leave the factory wiring alone and just run another gauge wire along with it?

If you add a second wire, that will work to recharge the battery - no problemo.

However, if ever your alternator fails to charge then the idiot light in the cluster won't warn you.

Don't forget to upgrade the battery negative cable too - same guage as positive.

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Prepare your future. It wasn't the lack of stones that killed the stone age.

why wouldnt the "idiot" light warn me? Right now the battery's factory ground wire is the same as the alternator wire running to the battery. I cant remove that ground wire though because of how its ran, but instead I used a 4 gauge wire and ran it from the negative terminal to the strut mount tower using one of the bolts as the ground. So since I did that, could I now just run the same gauge wire from the alternator to the battery?

The idiot light won't warn you because it reads voltage out from alternator. If the battery cable you added feeds back to alternator, the idiot light could be fooled into thinking that the alternator is still charging. For example, if one or more of the output diodes have broken down then the feedback to the idiot light will keep it from turning on.  It's an unlikely scenario, I don't know what make model year we're talking about and no two cars are alike so yours might or might not display a discharge.

The important thing is that you cannot harm the electrical by upgrading - instead you'll improve it.

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Prepare your future. It wasn't the lack of stones that killed the stone age.

For upgrading the alt wires, my common procedure is add a 4 or 0 guage ground from the battery to the chassis, and add the same for the power from the charging post of the alt to the battery. Its probobly a good idea to leave the factory wires also, and then use a DMM to test the voltages at all locations for consistency. Hope that helps.

In my Haynes manual in the back where they show the electrical diagrams, the power wire shows a fusable link. Is that the diode?

No it's not a diode. A fusible link looks like a regular piece of wire but is actually a fuse to protect the circuit.

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Prepare your future. It wasn't the lack of stones that killed the stone age.

Ok. Could you explane to me about this idiot light problem then? Im alittle confused. You said that if I was to run another wire along with the factory wire, that my idiot light wont turn on, or something like that because I will be getting feedback through the other wire. You made it sound like that wire (factory one) has a diode which prevents that wire from having feedback. If that is the case, then I would need to install a diode with the new wire.

The diodes are in the alternator. Don't let it worry you. Just go ahead.

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Prepare your future. It wasn't the lack of stones that killed the stone age.