whats the best way? multiple batteries - help

[t-money 10+ year member]

i have a kicker zx1500.1 and a mtx 2300xw that i'm hooking up in my car.I have two yellow tops, one under the hood and one going in the trunk. For the power i have, do i run 0 guage from the amp under the hood to the one in my trunk, and from that battery run a piece of 0 guage with a inline fuse to the kicker amp, and then also run a piece of 4 guage with a inline fuse to the mtx amp? or do i run a piece of 0 guage from batt under hood to batt in trunk, then run a piece of 0 guage with a inline fuse to a distro block, and run two pieces of 4 guage to each amp? never had multiple batteries before so not sure which way is best. any help is appreciated.

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[jmanpc 5,000+ posts]

I would use 2 runs of 0 awg back to the trunk- one positive and one negative. Hook those to the rear battery, and run power wire for the amps from the rear battery. If I were you, I'd fuse both ends of the + wire.

 

[jmanpc 5,000+ posts]

Oh, and definately do the big three beneath the hood to get the most out of the second battery.

 

[t-money 10+ year member]

thanks for the help. Can i not just run a piece of 0 guage from the battery in the trunk negative to the body of my car(floor). I have done the big 3 already in 4 guage as well.

 

[blue 10+ year member]

thanks for the help. Can i not just run a piece of 0 guage from the battery in the trunk negative to the body of my car(floor). I have done the big 3 already in 4 guage as well.

Actually , there's a better way of doing this .....

All you need is a single run of 0 gauge to the trunk for positive and negative from the under hood battery. After hooking that to the batteries in the back , and making your jumpers from trunk battery to second trunk battery , draw the amp's positive from one of the batteries in the trunk , and the amp's negative from THE OTHER battery in the trunk. This way , the amp's are drawing current from both batteries equally. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Using both positive and negative runs to the trunk is better than just positive. For grounding, the resistance of the car's metal will be higher than the resistance of quality copper wire, thus making the dual runs a better idea.

Also , you need to go ahead and upgrade the big three to 0 gauge also. If the audio system warrants wire this large , then your big three will need it too.

 

[t-money 10+ year member]

thanks for the replies guys. So both of you agree that i should run one 0 guage wire from one batt pos to other batt pos and also run one 0 guage from one batt neg to other batt neg. But you're also saying that i should run the pos from one batt to the amp and the neg from one batt to the amp. never heard of doing it that way before but i'm open for suggestions. just want to do this the right way the first time.

 

[blue 10+ year member]

thanks for the replies guys. So both of you agree that i should run one 0 guage wire from one batt pos to other batt pos and also run one 0 guage from one batt neg to other batt neg. But you're also saying that i should run the pos from one batt to the amp and the neg from one batt to the amp. never heard of doing it that way before but i'm open for suggestions. just want to do this the right way the first time.

Sorry about that .... I mis-read and thought you have 3 batteries. I would definitely run both pos and neg runs to the trunk , but disregard what I said about the pos and neg to the amps coming from two different batteries ......

 

[phantom240 5,000+ posts]

I was thinking something similar. Im gonna go with one in the hood and one int he hatch...

So whats wrong with running the negative wire from the hatch battery to a good ground?

 

[sku 10+ year member]

I'm confused...why not just ground the battery in the trunk to the car? Why run the 1/0 from the front battery to the trunk battery?

 

[sku 10+ year member]

haha you beat me to it

 

[phantom240 5,000+ posts]

haha you beat me to it

//content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif//content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif//content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 

[blue 10+ year member]

I'm confused...why not just ground the battery in the trunk to the car? Why run the 1/0 from the front battery to the trunk battery?

The metal on a car measures more resistance than 0 gauge copper wire from front to back does.

Also , when you ground in the back , you now have two ground points, and could create a ground loop or extra noise.

 

[phantom240 5,000+ posts]

The metal on a car measures more resistance than 0 gauge copper wire from front to back does.
Also , when you ground in the back , you now have two ground points, and could create a ground loop or extra noise.

Good point. But the battery under the hood is grounded to the car... And running wire to the other battery would create even more resistance the way i understand it.

 

[sku 10+ year member]

The metal on a car measures more resistance than 0 gauge copper wire from front to back does.
Also , when you ground in the back , you now have two ground points, and could create a ground loop or extra noise.

Huh? The metal in the car's frame has more resistance than 1/0? I don't think so but not sure how to prove it....

 

[phantom240 5,000+ posts]

Huh? The metal in the car's frame has more resistance than 1/0? I don't think so but not sure how to prove it....

Ill see what my dad has to say. He studied electronics in teh navy and has more books about that shit than i could ever read.