replacing factory 10 gauge wire did wonders

[QUIP'6']

was always having voltage problems. when i first start my car the scanmaster would read 14.1 to 13.9 volts and then when up to temperature the volts would show 12.9 to 13.4 and when i put on the rear defroster and try to use the wondows the volts would show low 12's to high 11's this is my 3rd alternator in 4 yrs and they all showed the same. these are napa alternators. well today i cut off the 10 gauge wire from battery to alternator and put on a stud on the negative and ran a 4 gauge wire from battery to alternator and now my car idles like a dream and the volts dont change even when warm they stay at 13.8 to 14.1 and when i hit the windows they are faster and the astro roof flies. also when i put on the lights and the ac and the rear defroster the volts on the scanmaster drop to 13.5. another thing is the wire stays cold. the 10 gauge wire would get real warm as so did the alternator. i hope this helps

 

[realspartan]

I did the same thing last year because I hooked up a new radio, amps, speakers and subs. It is a must. I have both the 10 gauge (from factory) and the 4 gauge I installed from alternator to battery.

Regards,
Realspartan

 

[6APPEAL]

Replace mine many years ago with 4 guage.
John

 

[challengermike]

Wow this thread is great,i have been chasing this same problem for 2 years now.So you can just run another wire(4 gauge)from the batt to alt and still leave the factory 1 hooked up correct?I would be happier than a pig in poop if this fixes my problem.

 

[Adam Connell]

Heck yeah, I get low voltage warnings from time to time until the car "warms up" as well... time to take a look under the hood and see what's in there.

So where can I pick up the stuff to do this?

 

[87gninpa]

Sounds like a great idea. Anyone have any pics of the install?

 

[Just a Six??]

When I did my trunk mount 10+ years ago I realized I needed bigger wire to starter from alt & also use 4 guage. I got it from a stereo shop for cars & they have some bad azz cables & connectors.

 

[turbobooster]

r u guys referring about the red wire cable that goes from alt to battery?

 

[Buix893]

Yea...post pics. So all ya do is run a 4 guage wire from the alt to the POS terminal on the battery?

 

[QUIP'6']

i put a stud on the positive and ran a 4 gauge wire to the alternator and i put a stud on the negative and ran a 4 gauge wire to the fender for a ground

 

[challengermike]

Well i tried it on mine and its still the same,bummer:frown:

 

[GNVenom]

I'm wondering, WHY would anyone need to run a 200-240 amp alternator to their car?? Is everyone running dual Weldon fuel pumps? That'd be the only real reason you'd need it - and you would have to upgrade your battery (or batteries) to support it.

The factory OEM battery cable uses 8 gauge wire, not 10 gauge wire, to the alternator. The starter feed is 4 gauge.

The standard ground connection to the chassis is 10 gauge and the negative battery cable to the block is 4 gauge. If you've added current-hogging accessories to your GN, it would be wise to add an additional ground between the engine block and the chassis - use a BRAIDED flexible ground strap or arc welding cable with soldered terminals.

8 gauge wire will support 75 amps, 6 gauge, around 100 amps. With a fully charged battery, your stock alternator never delivers more than around 55 amps, even with every conceivable accessory turned on full-boat all at once. This would include low impedance injectors, high output coil, upgraded fuel pumps, power windows up all at the same time, electric seats moving, and so on.

That is, unless the battery is deeply discharged or has shorted cells. Then the alternator goes into overdrive.

You should never need any more than a 6 gauge cable connecting the alternator to the battery, even with a 200 amp alternator. I'd recommend 6 gauge if the battery is in the trunk, since it needs to travel maybe 14 feet to get there.

 

[Rich Gio]

wow this thread is great,i have been chasing this same problem for 2 years now.

x2!

 

[Roger]

Wow this thread is great,i have been chasing this same problem for 2 years now.So you can just run another wire(4 gauge)from the batt to alt and still leave the factory 1 hooked up correct?I would be happier than a pig in poop if this fixes my problem.

I don't recommend leaving the factory 10 gauge hooked up, troubleshooting might turn into a nightmare.

 

[Roger]

I ran 2 gauge wire tfrom alt to batt.

I recommend Caspers ground extender.

I run 140 amp alternator, mainly due to availabilty & $. 140 amp off a Chevy is easier to find & less expensive than 120 amp for the TR.

 

[challengermike]

I don't recommend leaving the factory 10 gauge hooked up, troubleshooting might turn into a nightmare.

I can unhook it and see if it changes.The problem hasnt really caused the car to die or anything,it bothers me more than anything.

 

[GNRick]

Well, John, you might not agree with my findings....my volt gauge always read low, like under 12 volts, when I had the A/C on, headlights on, and radio (with a couple extra amps) on all at the same time. This is at idle. When driving, volts were mid 13's. I just ran an 8 guage wire from battery to alternator (left the "factory" wire connected) and difference is like night and day. Volt gauge immediately ran up to near 14 volts, then after idle dropped to around 800rpm, gauge stayed at mid 13's with all accessories on. I'm very glad I saw this thread. John- I'm using your positive battery cable. Maybe you should offer one with a 4 gauge wire to the alternator?

 

[challengermike]

I don't recommend leaving the factory 10 gauge hooked up, troubleshooting might turn into a nightmare.

I disconnected the 10 gauge and no change.

 

[Adam Connell]

Ok I'll say it again... this forum has some wild misconceptions about amps, volts, and no concept of Ohms.

amps are not your problem if your voltage is low... voltage is what you need to make sure you're getting the right amount of power, amps are the actual power. If you dont have the voltage you need, you can throw all the amps at it you want and you'll never fix the problems.


But back on topic, bigger than needed wire will never create an issue.

 

[Adam Connell]

Guys, I did this yesterday as well! Holy **** what a difference!

Really no kidding, I am completely amazed at the difference... My best guess is that my battery was never fully charging and was a constant drain on the system... after a day of driving the difference is staggering.

I've got a manual fuel pump prime switch and the pump has never sounded this good on start up, my car also starts MUCH better... the power windows are noticeably faster, and the most alarming thing of all are my turn signals. They blink at a "normal" speed. They've always been slow, but I figured it was a flasher issue and since they worked I didn't care.

In other words, DO IT!

All I did was buy a regular positive 6g battery wire, cut off the ends, and bought the proper ends and that's it! The rest of the old major wiring has got to go as well...