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Battery Relocation Fuse Question

negativecamber

By negativecamber,
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negativecamber Collaborator

negativecamber

Posted
Posted

hey all

i am half way through a battery relocation in my s13 and after reading about 4 different forum articles i am hitting a wall.

i read that its best to use a fuse on the power cable (car stereo amp type), and have it as close to the terminal as possible. i have done this but it keeps on blowing as soon as i try and start the car. the acc is fine but the starting blows it. the fuses i got are 50amp rated and 60 is the biggest i could see in the shop. somebody has told me that the starter motor can draw anywhere from 100-200 amps during startup, but i havent seen a fuse big enough for that.

we tried to start the car with no fuse and it started no troubles. i am just concerned about a short or a fire if i run the battery with no fuse.

do many people here have fuses on their boot relocations?

FYI i have a 4 gauge cable for the power cable and a 6 gauge for the grounding in the boot.

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shanef Grand Master

shanef

Posted
Posted

you dont need to run a fuse, theres no way ur cable can get damaged if u reloacted it properly. When i did mine in my 32 gtr, i ran 0 gauge from the front, under the inner guard, through the firewall, under the carpet, under the rear seat, and into the boot to the battery. Also i've got a 2 gauge ground on the battery.

You will have to use larger gauge wire to get the correct ampage to ur alternater :)

negativecamber Collaborator

negativecamber

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  • Author
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when we started it with no fuse, the 4 gauge was enough to get 12.x volts on acc and to start the car so i dont think i'll need to get a bigger gauge cable yet. i dont like wastin money on things i just paid for :)

the only place i think my power cable could get damaged is the firewall, there is no grommet there anymore.

shanef Grand Master

shanef

Posted
Posted

just grab a can of that expanda foam and she'll be right.

i'd be worried about what damage its doing to both ur battery and the alternator. for piece of mind, check what voltage ur getting down at the alternator when u fire it up.

negativecamber Collaborator

negativecamber

Posted
  • Author
Posted
just grab a can of that expanda foam and she'll be right.

i'd be worried about what damage its doing to both ur battery and the alternator. for piece of mind, check what voltage ur getting down at the alternator when u fire it up.

what should it be to be safe?

am i just checking to make sure it hasn't dropped too much?

sorry for the noob questions but these things weren't in the relocation articles.

Zathris Contributor

Zathris

Posted
Posted
what size cable are you running mate?

cant remember off the top of my head, will check tomorrow, i went to battery factory and got the second thickest stuff they had there...it was about 1cm thick. oh yeah another note, get more cable than you think you will need, the guys at battery factory convinced me i only needed 4m, ended up using closer to 6m

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