I want to relocate my battery to my trunk and I could use advice. There's not much in general about it but was wondering if anyone knew anything. I'm making room for a cold air intake right now.

 

The install is similar in difficulty to installing a car audio amp. Short version is that you mount the battery in the trunk, run short piece of large gauge ground wire to a solid piece of metal. Then you run a large gauge power wire under the trim and carpet up the drivers side of the cars interior, through the hole in the firewall, then reconnect it where the factory power wire went to. Easiest way I've found to do this is with a distribution block for car audio. That let's you put your large gauge wire in one side, and your smaller gauge wires out the other to your altenator, starter, fuse box, etc.

You also have to be careful to use a battery that's meant for use inside a car (completely sealed, non vented), or to buy a battery box that is sealed and vented outside the car.

Search summit racing or jegs for a battery relocation kit, they have a lot of options. Make sure it is mounted solidly as it'll ruin your day if it breaks free in a wreck.

With that said, there are a few downsides:
-you may gain a little power from the cai, but you're going to add a good bit of weight from the huge gauge wire and battery box
-many drag strips won't let you run without an external cutoff switch on a car where you've done an aftermarket battery relocation to the trunk. You don't want to have to install an external cutoff switch on a daily driver, it'll look goofy.
-you'll be taking a good amount of weight off the drive wheels where it benefits you by adding traction
-obviously whenever you do electrical work with the battery, there is potential for a lot to go wrong as it has a lot of energy stored inside. Short circuits on large gauge wire connected straight to a battery are always bad news.


Just a few things to consider. There are a lot of potential drawbacks for the small hp gains of a CAI.