Dimming Lights
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Joined: Apr 2007
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From: Slidell, LA
The Big 4 gives the vehicle the ability to run energy through the vehicle more effectively. But is also meant as a pre-cursor to a larger alt setup. It normally helps in freeing up about 1hp (762w=1hp, if I remember correctly. Ive seen that number by a manu one time.) Now, thats why its always recommended. Especially since an alt is a necessary upgrade (if everything was done accordingly) if the system drain is more than 120% than the rated capacity of the alt. Anymore than that and damage becomes possible. Keep in mind the current draw of most vehicles (with all acc's on) is about 80-85% of the rated capacity of the alt. 130A alt lends to about the trucks max possible draw being about 110A. Leaving 20A. 20A is 360w@12v. At 120% gives 156A leaving 46A. 46A is 552A at 12v. Starting to see my points.
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Joined: Nov 2008
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From: se texas
The Big 4 gives the vehicle the ability to run energy through the vehicle more effectively. But is also meant as a pre-cursor to a larger alt setup. It normally helps in freeing up about 1hp (762w=1hp, if I remember correctly. Ive seen that number by a manu one time.) Now, thats why its always recommended. Especially since an alt is a necessary upgrade (if everything was done accordingly) if the system drain is more than 120% than the rated capacity of the alt. Anymore than that and damage becomes possible. Keep in mind the current draw of most vehicles (with all acc's on) is about 80-85% of the rated capacity of the alt. 130A alt lends to about the trucks max possible draw being about 110A. Leaving 20A. 20A is 360w@12v. At 120% gives 156A leaving 46A. 46A is 552A at 12v. Starting to see my points.
so your saying not neccesary unless you plan on upgrading your alt or want a 1 hp increase(lol). whats 1 hp goin to do for you? or if your current draw excedes the rating of your alt well that is a given on that you will deffinitly notice when your bat starts going dead all the time because your alt wont carry everything.
but in reallity who uses there full capacity and more of there alt continuously everytime they drive there truck everywhere they go?
i have 2 40 amp fans mounted in front of my radiator that come on when the ac compressor kicks on or its really hot outside, and 2 1200 w amps and a 400 w. do i exceed the rating on my alt? yes, but in over a year of everything being installed i have not had any problems out of the stock charging system. not once. ha since i say this it will probally be dead tomorrow lol. do i turn up my stuff well of course thats why i put it in. does my voltage drop of course. but i do not plan on changing out my alt just because my lights dimm. if it fries ill upgrade it. but hell i could put a 250 amp alt in and my lights will still dimm just like they do in my car after i put in a 250 amp alt and upgraded the wire. simply because it takes the voltage regulator a min to adjust to the extra current needed by the amps.
but really whats the point on the big 3 or 4 unless you plan to upgrade the alt. that is really the only reason it should be done. for dimming lights nah its not going to get you more amps out of your stock alt to power everything.
i guess i just said this because everytime i see on a forum that someone has their lights dimmimg everyone wants to say upgrade your wire which is really only needed if they plan to upgrade the alt unless their factory grounds just suck.
Last edited by jrfonte; Mar 8, 2009 at 06:01 AM.
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Joined: Apr 2007
Posts: 4,494
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From: Slidell, LA
what was you trying to say right there?
so your saying not neccesary unless you plan on upgrading your alt or want a 1 hp increase(lol). whats 1 hp goin to do for you? or if your current draw excedes the rating of your alt well that is a given on that you will deffinitly notice when your bat starts going dead all the time because your alt wont carry everything.
but in reallity who uses there full capacity and more of there alt continuously everytime they drive there truck everywhere they go?
i have 2 40 amp fans mounted in front of my radiator that come on when the ac compressor kicks on or its really hot outside, and 2 1200 w amps and a 400 w. do i exceed the rating on my alt? yes, but in over a year of everything being installed i have not had any problems out of the stock charging system. not once. ha since i say this it will probally be dead tomorrow lol. do i turn up my stuff well of course thats why i put it in. does my voltage drop of course. but i do not plan on changing out my alt just because my lights dimm. if it fries ill upgrade it. but hell i could put a 250 amp alt in and my lights will still dimm just like they do in my car after i put in a 250 amp alt and upgraded the wire. simply because it takes the voltage regulator a min to adjust to the extra current needed by the amps.
but really whats the point on the big 3 or 4 unless you plan to upgrade the alt. that is really the only reason it should be done. for dimming lights nah its not going to get you more amps out of your stock alt to power everything.
i guess i just said this because everytime i see on a forum that someone has their lights dimmimg everyone wants to say upgrade your wire which is really only needed if they plan to upgrade the alt unless their factory grounds just suck.
so your saying not neccesary unless you plan on upgrading your alt or want a 1 hp increase(lol). whats 1 hp goin to do for you? or if your current draw excedes the rating of your alt well that is a given on that you will deffinitly notice when your bat starts going dead all the time because your alt wont carry everything.
but in reallity who uses there full capacity and more of there alt continuously everytime they drive there truck everywhere they go?
i have 2 40 amp fans mounted in front of my radiator that come on when the ac compressor kicks on or its really hot outside, and 2 1200 w amps and a 400 w. do i exceed the rating on my alt? yes, but in over a year of everything being installed i have not had any problems out of the stock charging system. not once. ha since i say this it will probally be dead tomorrow lol. do i turn up my stuff well of course thats why i put it in. does my voltage drop of course. but i do not plan on changing out my alt just because my lights dimm. if it fries ill upgrade it. but hell i could put a 250 amp alt in and my lights will still dimm just like they do in my car after i put in a 250 amp alt and upgraded the wire. simply because it takes the voltage regulator a min to adjust to the extra current needed by the amps.
but really whats the point on the big 3 or 4 unless you plan to upgrade the alt. that is really the only reason it should be done. for dimming lights nah its not going to get you more amps out of your stock alt to power everything.
i guess i just said this because everytime i see on a forum that someone has their lights dimmimg everyone wants to say upgrade your wire which is really only needed if they plan to upgrade the alt unless their factory grounds just suck.
1hp = 746w.
Lets just look at your setup. 1200w = 120A, 1200w = 120A, and 400w = 34. Total you are pulling 274A at full tilt (w/o clipping, if you clip its alot more. Based at 12v). Lets say your truck charges at 13.8 (normal for these PCM controlled trucks). 1200w = 87A, 1200w = 87A, and 400w = 29A. Total = 203A. Still grossly exceeding the rated capacity of the Alt. Now, under a load like that the alt will not be able to keep up. Therefore, the voltage in the truck will decrease and the battery becomes a storage bank. When this occurs, you start getting back to the original 12v numbers. This causes the amps to pull harder and lights to dim even more.
Now, resistance is defined as a opposition to a change in voltage. So, resistance is going to try and decrease the voltage as much as possible (why we use a resistor to defeat turn on pops for the Audiophile system). Lets say the stock wiring is from a 2004 and is starting to corrode. So, its now giving us a 1.2 ohm load.
Ill finish this later.
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Joined: Apr 2008
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Hey Low_e.....
I bet for the split second when you saw that I posted again, you thought you were going to be going back and forth with jrfonte, and me too !
But no. Honestly, I see what your saying, and yes, as a precursor to an upgraded amp..... and done with 4 gage... I do see some benefit of doing the Big 3 (or 4).
Of course the fact that I used 1/0 with a stock alt..... Doh !
See, I was thinking about my network of four, 300 amp alts later on ;-) LOL
Peace,
Fish
But no. Honestly, I see what your saying, and yes, as a precursor to an upgraded amp..... and done with 4 gage... I do see some benefit of doing the Big 3 (or 4).
Of course the fact that I used 1/0 with a stock alt..... Doh !
See, I was thinking about my network of four, 300 amp alts later on ;-) LOL
Peace,
Fish
A big fan of do it once and be done.
Thread Starter
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Member
Joined: Dec 2008
Posts: 10
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From: Houston
SOB so you guys telling me i just wasted some money on this big 3 upgrade? unless i buy a new alt? does any1 know the pricing range for a high output alt?
or would it be cheaper to upgrade my bat? or add a second one?
i don't plan on putting too much into this truck because im only keeping it for about another year.
or would it be cheaper to upgrade my bat? or add a second one?
i don't plan on putting too much into this truck because im only keeping it for about another year.
Technical Article Contributor
Joined: Aug 2006
Posts: 7,862
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From: Northern California
that chits useless on a stock charging system the alt's only capable of putting out so many amps and the factory wiring will handle all of those amps safely no problems. (if it couldnt then auto makers would be having alot of recalls on burnt wiring in factory vehicles).just because you increase the size of the wire does not mean that the stock alt will magically output more amps than it was designed to without upgrading it with bigger rectifiers and changing out the windings.
i had the lights dimming in my truck and did yalls suggested upgrades "the big 4" didnt do chit lights still dim alt still only puts out so many amps.
i had the lights dimming in my truck and did yalls suggested upgrades "the big 4" didnt do chit lights still dim alt still only puts out so many amps.
Senior Member
Joined: Apr 2007
Posts: 4,494
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From: Slidell, LA
SOB so you guys telling me i just wasted some money on this big 3 upgrade? unless i buy a new alt? does any1 know the pricing range for a high output alt?
or would it be cheaper to upgrade my bat? or add a second one?
i don't plan on putting too much into this truck because im only keeping it for about another year.
or would it be cheaper to upgrade my bat? or add a second one?
i don't plan on putting too much into this truck because im only keeping it for about another year.
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Joined: Jan 2006
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From: my apartment
second battery needs to be same as the first
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Joined: Apr 2007
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From: Slidell, LA
The First and Second batts in order not to add a battery isolator needs to be identical the first battery. Im talking, same voltage, same batch, etc. Otherwise they will drain each other dead.
Roll with a Yellow top Optima battery. For the JL set up I used to have in my truck, I also had two Kohl Audio 8 Farad capacitors. They assisted with my amp minorly but all the same it helped. Now that I dont have a system I use one of them to operate my CB radio. Usually one Optima battery is good enough but if you want to run two why not...