I've always read that for least resistance it's not so much the size of the wire as it is the number of strands in it. The more strands (finer) the less resistance, but that's just what I've read too.

 

That's true, at least for AC. It's called the skin effect. AC will have more dense currents on the outer edge of a conductor, and less the deeper you go. I have no idea if the same principle holds true for DC.

Either way, I used welding cable, so it's super fine threads

 

How did you go about attaching the lugs on the end? From what I've seen they appear to take a really large crimping tool, or did you solder them in place?

 

My friend let me borrow his crimping tool. It's a device you set the lug and wire in, and there's a plunger you hit with a sledge hammer a few times to put the crimp in the lug. Never seen that style before, but it seemed to work pretty well

 

So, big three is complete. Transmission seems to not be toasted, and I got a little figuring out done for adding the second battery.

It's not made up permanently yet, and this battery is slightly shorter than what will be in there eventually, but it's proof that a second battery can fit under the hood of a second gen Blazer


Still need to do a little more tweaking to the battery tray and get it bolted solid.

Also, my buddy wired up and mounted the switch to control the solenoid for me


So, it's a three position switch. The "regular ***" position will be the normal, keyed on solenoid operation. Batteries are tied together when running, isolated when off. "24 Volts!" triggers the solenoid off the second battery, in case the main is too dead to operate it. Allows for self jump starting without ever leaving the drivers seat. Not labeled is the middle position, which completely isolates the batteries, regardless of key position. Might be useful for trouble shooting, or saving the aux battery in an extended cranking situation.

(I know two 12V batteries in parallel is still 12V, and not 24V. It's just a joke, and to troll people)

 

Are you going to use a normal battery tie down for the second battery to hold it in place?

 

I still need to figure out a battery tie down. I'll be honest, my stock battery doesn't have any type of tie down, hasn't since I got it, and I've gotten by. But now, with the off roading, I need to figure something out.

I'm not a big fan of the wedge type system where it holds it down at the bottom. I prefer the strap/bracket that goes over the top.

 

Got the positive cable for the aux battery all finished



Top left goes to alternator, from there to the 200A solenoid. Directly into a 200A fuse, then to the positive terminal of the aux battery

 

I asked about the battery tie down because I see you're using a top post battery. It may come in contact with the hood if you hit a good bump. I also prefer the straddle tie down.

 

I'll have rubber covers over the terminals and posts, the main battery that I converted to top post is already like that.

But you do bring up a good point, I never though about it making contact with the hood