Battery Wire

[rebelyell]

I'm wanting to relocate the battery to the trunk, bypass ammeter and follow the rest of MAD electrical's tutorial on the charging system upgrade. I can get a battery tray from summit, the fusible links from MAD, all the electrical connectors/solder/tape/shrink tube from Home Depot, but the one thing I'm clueless on is the 1/0 battery wire.

https://www.wireandcableyourway.com/1-0-welding-cable-class-k.html
I'm assuming this will work? 25ft for the positive and 12' for the ground to the trans? And where on an A833 could I ground this?

[HP_Cuda]

Lower resistance requires solid core wire not stranded.

Just think of the length of wire you will run, the (R) will kill you. 

[rebelyell]

OK. Got it. I'll look for solid core.

[PlumCrazyRTSE]

Lower resistance requires solid core wire not stranded.

Just think of the length of wire you will run, the (R) will kill you.

Well, not really.  The reciprocal of the resistance of those many individual strands add together for a very low total resistance (1/Rtotal = 1/R1+1/R2+1/R3+....).  If the wires are made of the same type metal and the total cross section of the stranded wires is equal to the cross section of the single solid wire, then their dc resistance will be equal.  The advantage of the stranded is that it's more flexible.

[dodj]

Lower resistance requires solid core wire not stranded.

Stranded is higher ampacity and lower resistance for a given diameter. And more durable.
For your battery relocation I would use 1/0 welding cable. It is fine stranded, flexible and durable. 

[HP_Cuda]

All things being equal and we are not talking about AC, the only thing that matters is the total cross-sectional area of the conductor.

So is the total cross section of stranded > solid core wire. There is the rub.

Lower resistance requires solid core wire not stranded.

Just think of the length of wire you will run, the (R) will kill you.

Well, not really.  The reciprocal of the resistance of those many individual strands add together for a very low total resistance (1/Rtotal = 1/R1+1/R2+1/R3+....).  If the wires are made of the same type metal and the total cross section of the stranded wires is equal to the cross section of the single solid wire, then their dc resistance will be equal.  The advantage of the stranded is that it's more flexible.

[HP_Cuda]

Here is some downsides to using stranded:

- For preventing electronic interference, however, stranded wire holds a disadvantage because the air channels between strands magnify the skin effect caused by magnetic fields on the surface of the wire. Forget that radio you wanted to install.

- During use: since the strands are thinner your chances for breaking wires internally goes way up.

Solid core gives you:

- Solid wire is the wire of choice for outdoor or rugged-duty applications which may expose the wire to corrosive elements, adverse weather condition or frequent movement.

[Chryco Psycho]

Good luck using a 1/0 solid wire , it will be tough to bend & fit
I generally use welding cable , it is flexable & will handle high load has a very thick coating to resist abrasion

[HP_Cuda]

Btw, I never said use 1/0 solid wire, that was the OP's choice.

Here is another good read - especially if someone is thinking of running two wires from the front to the back.

https://www.w8ji.com/battery_wiring.htm

(spoiler - it's a no no)

[rebelyell]

Stranded is higher ampacity and lower resistance for a given diameter. And more durable.
For your battery relocation I would use 1/0 welding cable. It is fine stranded, flexible and durable. 

That's what I thought. I figured all welding cable was stranded. The original battery cables are stranded. The cables going to the battery under the back seat of a new challenger are stranded. I know there's going to be a long travel from the alternator to the battery and that's why I'm wanting to use 1/0 awg welding wire. It should be flexible enough to run it where I need it and still get the job done.

[dodj]

I use 1/0 motor lead wire (similar to welding cable but with finer strands and tinned) and have had no issues. Terminating the larger wire to the starter can be a challenge.
Finding a terminal for 1/0 wire with a stud size that matches the starter is the hard part.

[rebelyell]

https://www.summitracing.com/parts/pco-4438kt/overview/

This is the post that will adapt a 1/0 gage wire to the starter relay.

[PlumCrazyRTSE]

Stranded is higher ampacity and lower resistance for a given diameter.
[/quote]

Only for AC current because of the skin effect.  For DC current, stranded and solid of the same diameter would be identical.

[dodj]

Stranded is higher ampacity and lower resistance for a given diameter.

Only for AC current because of the skin effect.  For DC current, stranded and solid of the same diameter would be identical.
[/quote]
Well, we are really pointing out EXTREMELY small differences between ac and dc. When the resistance over a kilometre of 1/0 stranded is like 0.3 or 0.4 of an ohm.......so not really an issue worth considering.
And using solid in a car electrical system is not a good idea - vibration with solid wires = broken wires. (plus I don't think you could even buy solid in an appropriate size if you wanted to, let alone bend it)
So welding cable is the op's only real choice. If you had some extra $$ to spend, you could get DLO, diesel locomotive cable which is a really durable exceptionally fine strand wire meant for very high DC current carrying ability needed for locomotive motors. It has the highest ampacity for a given diameter that I know of. 4/0 = 510amps

[YellowThumper]

At the end of the day use the stranded welding cable. It has been proven to work well. That is what I used with no issue. For me. I ran it to a bulkhead on an inner fenderwell. From that the starter and alt charge connects as well.
If you are going to get into newer electronics. I suggest while you are at it. Run a ground cable up front as well instead of just grounding to chassis in the back.

Mike.