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Hey guys, so today, I thought I'd eliminate all chances of a bad ground, by running 0 gauge from the battery straight to the wires that used to be grounded to the battery. My symptoms now include startup at mid 14V while idling, till I give it gas, and then the volts drop to a steady mid 11. I'm out of ideas. Could this still leave a possibility for a bad ground? Could a positive wire cause this?
 

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With the engine running, headlights and heater blower on, check the voltage drop between the generator body and the negative battery post (post, not the terminal connector). In a perfect world it would be 0.0 V, in our world no more than 0.5 V--and that would be not good.

If it is more than that then there is a bod ground somewhere between the battery post and the generator body. Check the voltage drop across every connector you can get at (even between the post and the terminal connector) to find out where the poor ground path is.

Next check the drop between the generator output terminal and the positive battery post. Same as above; perfect would be 0.0 V and 0.5V or more is not good. Same process, check the voltage drop across every connection 'tween the battery post and the generator output.
 

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are you having an alternator issue? what is the problem your trying to correct? if your giving the car gas and you loose voltage then your alternator is going out.
 

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The problem could very well be a bad generator, easy enough to have it tested at any FLAPS.

However also the regulator (in the generator) has to accurately know the battery voltage. If either the ground or +12 V paths between the generator and the battery are poor the regulator can get confused and fail to proper control system voltage as system load changes..
 

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Discussion Starter #6
Yeah I had ford test everything and they said battery, alternator, and charging system are good. They recommended a capacitor for my amp, but i've unplugged the amp and have the same issues, so that can't be right. PA Performance checked the alt and said it's 100% as well. I had to add a 4 gauge wire for the new alternator, which in turn acts as a bigger gauge wire between the alternator and junction box. I've got 0 gauge positive from the battery to the starter post, and then the stock wire from the starter post to the junction box. Could upgrading that wire to carry more current help or is that just preventing more power benefits from the HO alternator?
 

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Yeah I had ford test everything and they said battery, alternator, and charging system are good. They recommended a capacitor for my amp, but i've unplugged the amp and have the same issues, so that can't be right. PA Performance checked the alt and said it's 100% as well. I had to add a 4 gauge wire for the new alternator, which in turn acts as a bigger gauge wire between the alternator and junction box. I've got 0 gauge positive from the battery to the starter post, and then the stock wire from the starter post to the junction box. Could upgrading that wire to carry more current help or is that just preventing more power benefits from the HO alternator?
Have you done voltage drop tests as described above? They will quickly reveal any wire capacity issues, though over a 6 foot run 4 ga is good for 200 A @ 13.8 V; 0 ga will handle 400 A over a 6 foot run.

Is there a good ground connection between the battery and the block? The return path for generator output is through the block...

The generator will only output as much power as is needed to charge the battery and power whatever loads are active. If the battery is good and the loads are as they would be on a stock setup then the new generator will not deliver any more power than would the OEM unit.
 

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I'm just going to say now if u r having these voltage issues with a system, a capacitor is going to help. I suggest doing the big 3, a second battery, more runs of wire. And if after that it is still bad u may need a high output alt.
 
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