Originally Posted by lvw
Nice writeup. OP, did you use larger wire or put any fuses on your setup? I am thinking about doing something like this on my 91. I am still running my AC also.l
I did use larger wiring. I don't believe it was strictly necessary given the amount of eletrical load I currently have, but I wanted headroom to add things in the future.
I left all the OEM wiring in place for redundency. I ran 1/0 gauge wire as follows:
battery to starter
starter to distribution block
distribution block to an auxillary fuse panel that I bought
distribution block to alternator
battery to chasis (trunk wall)
battery to power plant frame
alternator case to chasis
There were already two holes from the factory (thanks Mazda!) in the passenger side trunk tunnel. I just had to bore them out a bit to get the fat wire to fit.
The closer hole required a 90 degree drill adapter, they're pretty cheap on Amazon and come in handy now and then. I bored out the hole closer to the front of the car from the bottom with a drill extension and a hole saw.
I put some rubber grommets on the holes and smeared Permatex in order to keep moisture out.
300 amp fuse on the positive wire to the starter.
I also added a 150 amp fuse to the OEM positive wire. I felt this was necessary because it connected with my wires at the starter, so if anything went wrong with mine and the 300 amp fuse blew current could still flow unrestricted throught the OEM cable.
Here is the fused distribution block
There is a 150 amp fuse connecting the alternator to the starter/battery, and another 100 amp fuse connecting the starter/battery to the auxillary fuse panel.
I relocated my windshield washer fluid bottle and used the bracket to mount the second panel:
Cover to protect the distribution block
Right now I only have my HIDs connected to the secondary fuse panel, but I'm excited to add more gadgets. It will be very nice to have a go-to place to tap +12V and have all my fuses in one location for things like a larger horn or LED lights.
Fair warning: Not very experienced, all this might be really dumb.