Battery relocation

[SQF]

Battery relocation.

Why do it? More room up front for other items (MSD or IC sprayer perhaps?), it also helps add weight to the rear (for those concerned about weight distribution).  

How to->  Well, first off this is not the end all do all.  There are other ways to complete the task. This is just what I decided to go with. I have included a link to a Yahoo folder with many pictures to aid you.    

I decided to build my box using heavy gauge steel, aluminum and threaded rods for tie downs.  I coated the interior of my battery box w/ auto undercoating to help reduce vibration and the chance of conductivity should for some reason the battery slide.  Boxes are available through many vendors should you decide to go that way.  

   Once my box was built I ran 2ga welders wire from the engine bay to the rear of the car.  You MUST use welders wire  as solid or thick braid wire will not withstand vibrations from driving.  Any welding shop will have it in several gauges and will know what you are asking for.  Through voltage drop charts (thanks mike c.) I determined that my car would be fine w/ a 6ga wire but I decided to go w/ 2ga just in case.  It was not that much more expensive.  I ran the wire along the top of the drivetrain tunnel using cable ties (ziptie w/ a head that allows a screw to be passed through it to secure it).    

     Once the wire was run from front to rear I began the installation of the box itself.   I removed the hatch liner to expose the screws to the sub-floor.  With the liner removed I set my battery box in place to see how the box would fit.   I wanted to set my battery as low as possible (hatch shelf  clearence“issues”), so I set the box in place to see how much of the sub-floor I had to remove.  Take into account the space needed for the side liner (its position is inset on your sub-floor).  I then traced the box onto my sub-floor to mark the section to be removed.  With that completed I removed the entire sub-floor from the car.  (Under the sub-floor is the control unit for your ABS system. If you are keeping your ABS you must find a new home for that control unit.   I mounted my ABS control to the side of my battery box and ran the harness through a factory hole in the sub-floor to the control unit.  Next step was to cut out the section of sub-floor needed to allow room for my battery box.   Due to the fact that the sub-floor lost rigidity I took some left over steel and bent brackets to support the sub-floor on each side of the opening, screwing the brace to the chassis and the sub-floor.  If you are not using a sealed gel battery (ie. Optima) then you must run a vent through to the outside of the car.  This will keep the  gasses from leaking into your car (charging batteries produce hydrogen, you don't need that in the car).  I ran a 1/2" vinyl tube through the bottom of my box and through a hole I had drilled in the floor of the car. Be carefull to avoid drilling a hole into items below the floor (like the gas tank) and keep your vent away from exhaust heat sources.    

     With the battery box resting nicely in it’s new home I turned to the wiring portion of the relocation.  I decided to ground my battery to a rear frame bolt which holds an exhaust bracket.  I ran 2ga wire from the battery box through the spare tire well drain hole and attatched a copper electrical ring connector to the end of the wire that was going on the frame bolt.  If you are running wire through any holes in metal use rubber grommets to avoid sharp edges coming in contact with your wires.  To attatch a conductive ground I removed the bolts holding the exhaust hanger in place.  Next,  wire brush clean the exposed bolt/stud (until paint is removed and metal is exposed).  I decided to apply  bulb grease to the stud.  Once that was completed I bolted the grounding wire to that stud.  mike c. recommends adding a star washer (washer with teeth on the inside of the ring) to ensure a good bite into the metal.    

     Nearing completion!  Now the box was in place, the ground was set and I faced the positive lead dilemma. Your positive battery lead has the alternator feed as well as your main fusible link and several other wires powering vital systems.  I decided to use a large aluminum but-connector to connect these wires to my 2ga feed.  I clipped all of the positive lead wires, stripped the needed amount of shielding and crimped them into the butt-connector.  I applied electrical bulb grease to the inside of the connector as well as the wires.  You can also choose to connect the wires by using a power distribution block.  Such blocks are available at many stereo installation stores.  They consist of a solid block with a series of set screws.    Once the box is secured in place, the ground is ready and your positive feeds are connected you can move the battery to the hatch.  Connect your battery, put your case top in place and off you go!  I have experienced no power drain or voltage loss issues using this method.  If you have any questions feel free to PM or email me.  

Mike SQF

Pics->  

http://photos.yahoo.com/bc/sqfny/lst?.dir=...tion&.view= t