Battery Relocation

bambam 06

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Thank you for your answer. I will not be using a battery isolator cut off switch (i don't race the car) I have a 1/0 welding cable running from the trunk battery to the front where the OEM battery used to be, that is where the BMW battery distribution block will be installed. I will transfer all the OEM cables that were connected to the battery to the distribution block to keep it as OEM as possible. If i am doing anything wrong, please correct me. i will be doing the transfer in a couple of days. Thank you for your help.
 

DieHarder

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O.K., starting this project. Figured out it's simple to upgrade the starter/BEC cables, so those are going to 1/0.

Clarification on the two grounds that came from the battery to the chassis and the engine block. Now the battery will be grounded to the chassis in the trunk. Will running a ground from the block to the chassis be sufficient? Do I need to add another ground in the bay? Thx...

View attachment 81613

It should be electrically the same anywhere on the frame however if you notice low voltage output (<14v) across the battery with the car running then you may need to run a separate ground line directly from the neg post of the battery to the ground on the passenger strut tower. That will ensure electrical ground is at the same potential throughout the entire system. Conduct testing first. If you don't have to no need to go there.
 

bambam 06

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I did that, plus an additional one in the trunk. So hopefully it should be ok. Thank you for your input. The distribution block should arrive tomorrow.
 

scramblr

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It should be electrically the same anywhere on the frame however if you notice low voltage output (<14v) across the battery with the car running then you may need to run a separate ground line directly from the neg post of the battery to the ground on the passenger strut tower. That will ensure electrical ground is at the same potential throughout the entire system. Conduct testing first. If you don't have to no need to go there.

Thank you and to everyone else that gave inputs.

Got everything done. Voltage output is >14v across the entire car, but I'll keep an eye on it along with the battery charging.
 
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86GT351

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Shameless post. If anyone is interested I have a good Used Moroso Blue Plastic Battery Box available. 50.00 plus the ride.
 

JC SSP

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Yeah, if your tracking or racing every bit of shedding or moving weight around to 50/50 makes sense.

If I recall correctly, S197 GT has stock 52/48 weight distribution?
 

dustindu4

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Bringing mine out through the taillight lens I think.
 
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