Trunk mounted battery location for best suspension balance?

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BXSS
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Trunk mounted battery location for best suspension balance?

Post by BXSS »

Does anyone have any LSS corner weight info that could help me decide on where to mount the battery in the trunk of my LSS?

I know I want to mount it close to the rear seat (so that it does not sit to the rear of the strut towers), but am unsure which is best location to offset the drivers weight (the pass. side, or center) & get the most even weight distribution/balance overall.
94 Legacy SS
96 Impreza OBS
99 Impreza OBS-T
04 Sienna XLE Limited AWD
SemperGuard
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Post by SemperGuard »

Considering that your car weighs probably more than 3200 lbs by now, I don't think moving a battery that weighs maybe 25 or so is going to make enough difference, especially when you add in the weight from the cable you'll be running now.

Overall seems like too much trouble for not enough increase in performance. You could probably get better performance with just a lighter battery. But still, is it worth the money just to save 10 lbs from the battery? Saving the money and putting it to lighter wheels or better tires would be a much better use of time and money I think.
n2x4
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Post by n2x4 »

I agree with SemperGuard about the whole lighter wheels/better tires thing, but there are some advantages from relocating/switching the battery versus just removing 25 random pounds.

Battery weight is high on the car which impacts your center of gravity. The whole idea behind relocating it is to help with lowering the center of gravity. Also, our battery is on the end of the car. If weight is far from the center of gravity, the car is going to resist change in direction more (polar moment of inertia). Switching the battery around may help performance more than you might guess, but I do agree that sticky tires are definitely going to boost performance more.

But to answer your question, I vote for centered against the rear seats, though I don't have any data to back it up :-) .
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jamal
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Post by jamal »

I vote for lightweight battery.

I was so close to drilling speed holes in my bumper beam when I replaced it.
BXSS
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Post by BXSS »

1- The battery weighs 45lbs (red-top optima), even Civic batterys weigh more than 25lbs & I have had issues with these in the past on Subarus @ low temps.
2- The battery no longer fits in its stock location due to FMIC Tubing taking up some of its space.
3- A mini battery (hawker/odessey) can be used, but will not crank the car over when it is 20* outside.
4 - I'm not looking for any weight savings with the battery relocation, I'd rather not do it at all but I have to move the battery - so I may as well try to do it as best as I can.

The F-R weight distribution on these cars is like 56/44 or something like that so moving 1.4% (1% of 3200=32lbs) rearward can't hurt.

So my question remains center or p/s....
94 Legacy SS
96 Impreza OBS
99 Impreza OBS-T
04 Sienna XLE Limited AWD
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