Want to Finish 3G Install But Need Help

ram360

Founding Member
Oct 19, 2002
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Pennsylvania
I've been looking at all the 3G how to posts and nobody has a pic of the large 4g wire with fuse that runs from the 3G's post. Here's the rundown of what I gathered for wiring this thing up right

The one connector on the factory harness plugs right into the 3G (no need to modifiy it)

The white stater wire plugs into it's own terminal on the 3G

But what do I do for the 4G wire that's supposed to run from the 3G's post? I hear people mentioning fuses etc... but nobody has a pic of anything? Where do I connect this wire? I'm totally confused. Anybody see a problem with using 2G welding cable instead of the standard 4g. I have some laying around and would use that.
 
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I looked at that page before...Dunno I see some people use 2 12g fused links and others are using these huge ass 150A fuses? Doesn't seem like a 150A will do much good. With somehting that big by the time it trips it would fry the complete electrical system...seems like you might as well run the cable strait if your going to do that? Maybe I'm missing something? I still have no idea where that wire ends up either?
 
I'm running a 140 amp powermaster w/ a 4 gauge wire to a circuit breaker and then to the starter solonoid.

Here's a pic:
pic.php

I ran the wire down and mounted it to the front sway bar w/ wire ties and then ran it up to the circuit breaker.

I chose a circuit breaker so that I don't have to replace fuses if there are any problems.

I don't know if that's similar to the 3g or not.

I used a 6' long battery cable from a farm supply store, cut the battery terminal end off and crimped a ring terminal on; you can use a starter wire, which would be my choice in hindsight, but what I have works fine. Go to the auto parts store and look at different sizes of starter wires. You'll have to cut it for the circuit breaker anyway, so get one that's too long if you can - one for our cars would be fine.
 
i just finished my install this week, i ran 2gauge cable and a 175 amp inline fuse. the 2gauge runs from the steel stud on the back of the alt (with a ring connector, i had to grind down my 2gauge ring), runs thru the fuse, and over to the positive/hot side of the starter solenoid (follow the positive battery cable to its first stop). ive got a couple pics over in the talk section, though its kinda hard to tell what i did cause i tried to hide it as best i could, i wanted it to look as stock as possible.
 
Thanks guys, At least I now know where this thing is supposed to go. I do like the circuit breaker idea as well. where are you guys finding this enoumous fuses? I tried autozone and advanced and neither has anything over 100A. And back to my other question. It just Doesn't seem like a 150A will do much good. With somehting that big by the time it trips it would fry the complete electrical system...seems like you might as well run the cable strait if your going to do that? Especially if you think that you have an alternator with a maximum output of 130A yet you have a 150A fuse. The alt will never produce enough output to ever trip that fuse anyway. Seems to me like somthing smaller should be inline? At least that's my logic....
 
You can find the circuit breaker or fuses at your local stereo shop. Fuses dont tend to blow at exactly the rated limit. Normally they blow when a current surge reaches above the limit. Every fuse is different and will tolerate diffrent amounts of surge. Its safe to suggest that a fuse rated below somewhere below your alts max current wil be safe. I'm currently running a bit low at 100 amp fuse, but havent had problems yet. I will upgrade when I get a chance to stop by a stereo shop.
 
See WWW.partsexpress.com for the fuse & fuse holder.
Fuse @ $3.90 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=071-952

Fuseholder @ $5.80 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=263-630

4 gauge black wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-196

4 gauge red wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-194

4 gauge ring crimp terminals (package of 5) $3.25. http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=095-584

3/4 “ Black heat shrink tubing, 4ft length, $3.39
http://www.partsexpress.com/pe/pshow...number=082-058

3/4 “ Red heat shrink tubing, 4ft length, $3.39
http://www.partsexpress.com/pe/pshow...number=082-064

Pre-fab 4 gauge cables with lugs already on the ends are available in most auto parts stores. Look for the starter switch to starter cables.

The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges. Any car that has a 3G alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.
 
My fuse block was purchased from an Automotive stereo shop. It is a waterproof ANL style holder that I got for $10.00. I used a 150Amp fuse. My 4 gauge wiring runs along the factory path. I hid my fuse block behind the air box and then continued to run the new wire in front of the radiator, under the air box and up to the lug on the starter solenoid.
 
srothfuss said:
My fuse block was purchased from an Automotive stereo shop. It is a waterproof ANL style holder that I got for $10.00. I used a 150Amp fuse. My 4 gauge wiring runs along the factory path. I hid my fuse block behind the air box and then continued to run the new wire in front of the radiator, under the air box and up to the lug on the starter solenoid.


I just got back from my local stereo shop and they wanted $30 for the fuse block and $15 for a 100 amp fuse. For that much cash I can just get the PA Performance wiring kit. I might just order from the websites posted by JR and try to make my own.
 
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I used a fuse holder from a boating store. Thay had all kinds of different fuse holders and fuse sizes.
As far as the size fused used there are alot of different ideas but many use the 150 amp because it is easy to find and fairly cheap. I found that after my swap the car starts alot easier and I feel safer about the wiring. I also used 1/0 from the alternator to the solenoid. It was diffucult to hook up the starter solenoid but dont cheat on wiring size. At least 4 gauge. This has to be a easy swap but with so much different information out there it can be confusing.
 

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FWIW, Pep Boys here sells the wafer fuse holders and fuses. I dont know if that's a regional thing but it might be worth checking.
 
Would an inline 60A AGU fuse be enought for the 4g power wire from the alt to the starter relay? I've heard of people using two lengths of 12g fusable link so wouldn't a 60A agu fuse be comprable to that?
 
With a 130 amp alt & 4 gauge wire, the fuse size should be between 125-150 amps. It doesn't make sense to fuse circuit capable out outputting 130 amps with a 60 amp fuse.


Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps

That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!
 
ram360 said:
Would an inline 60A AGU fuse be enought for the 4g power wire from the alt to the starter relay? I've heard of people using two lengths of 12g fusable link so wouldn't a 60A agu fuse be comprable to that?
Are you going to somehow split the 4 AWG cable and use two fuses? I think we're not understanding something. :shrug:

In any case, JR is right. Get the right fuse and be done with it.
 
I believe what ram360 was getting at was the use of two paralleled 12 gauge links off of the single 4 gauge cable since a single 12 gauge link would not be enough and the largest fusible links I've seen have been 10 gauge. The two paralleled links would be the approximate equivalent of a single 6 gauge link.

Also, I don't believe an AGU fuse is designed to handle the thermal stresses and surges that it will encounter under the load of the main power circuit. The fuse element will flex and overheat eventually resulting in premature failure even if it doesn't blow.