yet another 3g idle charge thread. -

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yet another 3g idle charge thread.

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Old 12-17-2011, 12:32 AM   #1
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Default yet another 3g idle charge thread.

ok we go.i been searching and there are alot of threads about 3g idle charge issues and no concrete heres the deal.90 mustang gt,3g alternator(dont know if its 95 or 130 amp)stock pullies,4 gauge feed wire,4 gauge ground idle,no accessories on 13.4-14.2 volt range at about 40 amps.turn on lights,radio,blower on high,foot on brake and defrost,12.4 volts80-90 amps.then using the alternator tester at work,at 2000 rpms.117 amps at 14.5 car has no ac so ac isnt scared to add electric fans and ac system cause i dont wanna deal with killing the battery.also the battery is good.what is the fix to this?based on 117 amp max out out,does that mean i have the 95 amp pa performance alternator?would going to the 135 amp alternator fix this?do more amps mean more voltage?the d plug is correctly wired and the stator wire is correctly done as well.i have covered all the bases i can think of and have done alot of reading.thanks in advance.
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Old 12-17-2011, 01:47 PM   #2
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you're pulling 40 amps at idle with nothing on? jebus. i'd be lookin for whatever the frig is eatin so much power.

Last edited by mattdel; 12-17-2011 at 02:50 PM.
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Old 12-17-2011, 09:21 PM   #3
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12.4 volts with everything on at idle will not kill your battery.

Really, is your car ever going to see those particular conditions for more than a few hours.
Even with the heavy draw from ac and electric fans. Those accessories cycle on and off and you probably drive 90% of the time above idle.
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Old 12-18-2011, 08:03 PM   #4
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this is true.but i have been out on rainy nights and it gets scary watching that guage drop and all.i have been doing more research and im wondering if maybe putting the pulley from the factory alternator onto this one would bring it back up.i do know what is on the alternator now is the pulley that pa performance puts on it.also based on the numbers presented,would this appear to be a 95 amp alternator?would i be better off with a 130?
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Old 12-18-2011, 09:54 PM   #5
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heres another question for yall,where do yall have the fuse for the feed wire mounted?my area by the battery is crowded so im looking for a new spot to mount.
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Old 12-18-2011, 10:11 PM   #6
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I mounted mine below the air intake tube on the passenger side.
'89 GT, 5-speed, (because it's boring when the car does it FOR you), freshly rebuilt engine and tranny, GT-40 heads, Performer upper and lower intake, 130 amp alternator, K&N, alternator upgrade with Taurus fan, DCC fan control, subframes, Cobra R 17X9's.
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Old 12-19-2011, 07:30 AM   #7
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Never had a charging issue even with my accessories on.

My fuse is mounted inside my driver's side fender.
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Old 12-19-2011, 10:00 PM   #8
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+1 with what Mattdel said....

You are not gonna kill your battery though from adding everything. If you are worried though go through your car and upgrade your main grounds (battery to chassis and engine to chassis) and the main power wire. That alone will help with the charging on the car. Most of the time my gauge sits around the O and R on NORMAL and I have a STOCK alt running a Mark 8 fan, a small stereo system, and the headlights on. Yes at idle at a light it does tend to drop below half but most of the time and def while driving it is up there. But don't use some junk cheap *** battery though either.....
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Old 12-19-2011, 10:00 PM
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