Battery change or big 3

[deathcloud 6]

Ok so I got 2 major questions. Lets start off with the first one...

So I have been doing some reading and trying to understand batteries, amp hours, CCAs, and such. And I am lost.... I even watched that youtube video someone posted explaining it and I just was overwelmed with all the math/info. So here is one question for ya.

1st vehicle is a 1999 mustang GT. It has 1 4awg positive run to the rear and split in a distro block to a jl 300/2 amp and a phoenix gold zx350 amp. Ground in the trunk is also 4 awg as well. The problem is the lights dim. But when I hooked up a DMM to the battery in the front it read 14.4 volts and would drop to 14.1 at the lowest with the sub hitting. Now the crazy thing is at idle it was reading 14.4 which I thought was wierd.... I thought maybe lower lol but thats cool I guess. No big 3 has been done but I am thinking either I need to do the big 3 upgrade to prevent the lights from dimming.

Now here is the thing that made a light go off in my brain. When the car is off, it sits at 12.3 at the battery 12.1 sometimes. Does that mean it is time for a new battery? If so any recommendations? With all amps and their power ratings together add up to about 1000 watts. Do I need to have a new battery up front and have a rear battery in the trunk? Or is that overkill.

What battery would you all think I need? And why? I guess I am in the market for a new one and I want to be happy with my choice and have no dimming and give my amps the best power they can get.

I was thinking kenetic but I don't know which to get and they all say 12 volts. So I was confused by that.

Now question 2 haha sorry for this

I have a mazda 3 and I don't know the size alternator i have but I am guessing it is small. I also haven't done the big 3 yet but plan on doing it because I have a saz-1000D hooked up to an icon 12 inch sub. OMFG THIS THING HITS SO HARD. I will have a review of it in a bit. Anyways plan on getting a sax-100.4 as well. Now the question is I had a cap 1 farad that had a digital volt display on it but I have read in here caps are no bueno. So was thinking of doing a battery in the rear but again I have no idea which to get and what one will satisfy the needs of my amps. Or should I even get a battery in the rear?

Please don't yell at me and tell me to research or use the search function I did and I just don't get it. Hopefully you can steer me in the right direction with maybe some links to read so I can get a better understanding.

Thanks

[jcarter1885 995]

Before I even read this your gonna need to do the Big 3 regardless of what you will be running. We need to know the alternator's amp rating on each car if you want us to give you some accurate info.

[deathcloud 6]

Ok well I will save up for some 0/1 awg from knuconcepts cuz I heard that they have great wire and flexible too. Also need to save up for battery terminals as well. It kind of costs a lot to do the big 3 but I really want to get it done so I can see hopefully an improvement. But maybe a new battery will help some since it is only sitting at 12.3 volts which isn't right.

[jcarter1885 995]

The big 3 is relatively cheap compared to anything else in car audio especially dealing with electrical upgrades.

[deathcloud 6]

Yea well maybe when I get paid ill do the big 3 upgrade. But I have to find out what amp my alt is in the 2005 mazda 3 and 1999 mustang gt so I can have an inline fuze holder of 5-10 percent higher than it. right? I think that is the hardest part about doing it lol. I can never find out what my alt is and where to find out that info at.

But I really want to get it done in both cars so I can see what improvement it makes.

12 feet of 1/0 awg wire from knu is about 40 bucks. Then I still need an amp in-line fuse holder with the fuse. and new pos/neg bat terminals to house it. So its lookin to be about 75 bucks to do it. Around there.

[jcarter1885 995]

Yea well maybe when I get paid ill do the big 3 upgrade. But I have to find out what amp my alt is in the 2005 mazda 3 and 1999 mustang gt so I can have an inline fuze holder of 5-10 percent higher than it. right? I think that is the hardest part about doing it lol. I can never find out what my alt is and where to find out that info at.

But I really want to get it done in both cars so I can see what improvement it makes.

12 feet of 1/0 awg wire from knu is about 40 bucks. Then I still need an amp in-line fuse holder with the fuse. and new pos/neg bat terminals to house it. So its lookin to be about 75 bucks to do it. Around there.

Online they will tell you, you just gotta search for it or you can call your dealership. Naw you fuse to the wire and not the alternators rating. I have done the Big 3 two times so I know how much it costs, I said it isnt expensive like other car audio electrical upgrades that you can do.

[CrownVic 15]

You could save money and use welding wire, but its not very flexible at all.

Also my car has the dimming situation also although ive done the big 3 in 1/0 and my voltage is at 14.8 at idle and never drops below 14 at full tilt so i just leave it alone.

[audiolife 14]

I would do the big 3 before I did anything. IMO that should be part of amplifier installation.

[corrie3232 8]

on the 1999 mustang gt, if you had the factory Mach 1 system, you have a 130 amp atlernator, as for your batteries reading 12.3-12.1 volts with the car off, is normal, it should go up once you crank the car up. So you wouldn't need new batteries.

[jcarter1885 995]

on the 1999 mustang gt, if you had the factory Mach 1 system, you have a 130 amp atlernator, as for your batteries reading 12.3-12.1 volts with the car off, is normal, it should go up once you crank the car up. So you wouldn't need new batteries.

Yeah my batteries sit anywhere from 12.5-12.3 with no accessories on when the car is off and it sits at 12.1-12.3 with accessories on while the car is off.

[deathcloud 6]

You could save money and use welding wire, but its not very flexible at all.

Also my car has the dimming situation also although ive done the big 3 in 1/0 and my voltage is at 14.8 at idle and never drops below 14 at full tilt so i just leave it alone.

wait so you have done the big 3 and everything and it still dims? wtf? Thats not good. Maybe it means you need a better alt or something. Or maybe a battery in the back? I dunno.

[deathcloud 6]

on the 1999 mustang gt, if you had the factory Mach 1 system, you have a 130 amp atlernator, as for your batteries reading 12.3-12.1 volts with the car off, is normal, it should go up once you crank the car up. So you wouldn't need new batteries.

I dont have the mach1 system so i still don't know my alt rating. I will do the big 3, and also maybe change the car battery as it is 5 years old. Time for a new one. Thanks for all the help.

[johnecon2001 82]

You could save money and use welding wire, but its not very flexible at all.

Also my car has the dimming situation also although ive done the big 3 in 1/0 and my voltage is at 14.8 at idle and never drops below 14 at full tilt so i just leave it alone.

You're using the wrong wire if you think its not flexible.

[deathcloud 6]

Ok so here is my plan as of now.

1. Go to weldingsupply.com and buy their 1/O Welding Cable UltraFlex Orange I will buy 25 ft so I can do both cars (mazda 3 and 1999 mustang GT) and get it for a good price. 25ft for only 70 bucks seems like a good deal. Then perform the big 3 upgrade on both cars.

2. I did some research and watched the car audio 101 for alternator and battery. for those of you who don't know it is some crazy good info. And I had to watch it 3 or 4 times for it to soak in and make sense. Now I know why you want your voltage to stay CONSTANT at 14.4 volts! haha. Anyways I had to go find my user manual for my mazda but found out that it has a 90 amp alternator. So with doing the math and breaking it down it goes a little something like this...

saz-1000D + sax100.4 = around 1500 watts / .7 = 2142 watts

Then 2142 / 13 volts = total amperage needed which is 165 amps

Then we will subtract what my alternator produces in amps. So since I found out I have a 90 amp alternator we will assume that 40 percent of the alt is used for electrical accessories in the car leaving 60 percent of the alternators amperage for the aftermarket accessories. So 90 x .6 = 54 amps

165 amps - 54 amps = 111 amps

Now this is without including my battery that is in the stock location in the front. So I have to figure out how many amps it is producing and subtract it from 111 amps and then see how many amps I still need and maybe get a battery in the back of the trunk. But it is looking like a Kinetik HC1800 fits the bill and will be able to help out on my electrical system and also help keeping my amps fed with enough power to have their full potential and less stress on my alternator.

I totally get it now. It makes a lot of sense. It is way better to have your voltage at 14.4 without dropping because once it drops then there is an increase of amperage needed to get the maximum wattage. Example

1500 watts / 14.4 volts = 104 amps

but if it drops to 13.4

1500 watts / 13.4 = 112 amps

So you can see the increase of amps needed just to maintain maximum output of the 1500 watts.

Hopefully this will help anyone else out there.

Any criticism / more helpful tips needed. Am I in the right direction?

[CrownVic 15]

I guess i am then because unless your hulk hogan you cant make the wire do that. I got my wire at home depot.

[johnecon2001 82]

I guess i am then because unless your hulk hogan you cant make the wire do that. I got my wire at home depot.

That's the wrong stuff lol. That stuff is for wiring a home. Go to a welding supply store.

[deathcloud 6]

Yea when I was getting some stuff for my box build I was checking out the wire that they had at Lowes. And it is for home electrical lol. Probably not the most flexible stuff. So with that being said I deff need to do the big 3 and I plan on putting a battery in the trunk as well. probably a kinetik HC1400 in the back. But I plan on searching for a welding supply store first and see if they have some stuff around in my area. If not there is a high end car audio place that sells 0/1 awg but probably going to be a little more expensive.

with my car on, it is at 14.6 but when the sub hits it drops to 12.8 to 12.4 hence why I am getting the light dimming. I will do the big 3 of course first because it is the cheapest route, then the battery in the trunk will come next.