I'm move the battery to the boot on the right hand side using a BMR battery relocation kit.

I've run the positive cable thru the car interior under the carpet next to the right hand side sill panel.

I like the idea of having the hole a bit higher to keep is clear of the ground and exhaust, but a higher location might mean a sharper bend on the cable.

Any suggestions on the best place to drill a hole in the fire wall to get the battery cable to the starter motor?

 

What gauge wire are you running?

 

You can get through bulkhead fittings that insulate the current from the firewall and have a nice threaded connector on each side. I think Summit has them for an idea of what they are like.

 

I think it's 0 gauge. It's specialist copper battery wire I bought from a speed shop and is twice as thick as the original battery cable wire.

I've gone to a lot of trouble with the connectors and earth points to get plenty of juice for the starter.

 

I used the same thickness with the cable in the boot used for an earth.

As well as a terminal for the earth bolted into the body, I ran the metal self tapping screws used to support the BMR Battery box thru the black earth cable, giving it a couple of different earth points, some into the body panels and some into the sub frame.

Up front I'm still not sure what to do with the alternator wire. Either I can replace the cable from the fusable link with a new length run to the starter, of I can lead the old cable and starter cable in place and do it that way. Running a new lenth of cable for the alternator is more work but would look neater.