Charging wire from alt to battey

[Tony Shoaff]

I had to mount my battery in the trunk. What size wire is needed to run from the alt to the battery in the trunk to charge the battery? Thanks.

 

[TurboDave]

I had to mount my battery in the trunk. What size wire is needed to run from the alt to the battery in the trunk to charge the battery? Thanks.

For that distance, I wouldn't run anything smaller than a 4ga.

 

[Tony Shoaff]

Thanks

That is what I am running. Just making sure.

 

[SouthernCal GN]

0 gauge welding cable.

 

[TurboDave]

0 gauge welding cable.

I'm not so sure I'd run welding cable. I can't disagree with your gauge recommendation, although a bit overkill, but welding cable uses many many fine strands to make up the run. While this is great for welding cables (because of the AC component in the current) it's not the best selection for DC wiring.

 

[SouthernCal GN]

I'm not so sure I'd run welding cable. I can't disagree with your gauge recommendation, although a bit overkill, but welding cable uses many many fine strands to make up the run. While this is great for welding cables (because of the AC component in the current) it's not the best selection for DC wiring.

Good point- I'm fluent in most things mechanical, but chasing electrons is something I have to sit and figure out before I act- I've done the 120V dance a time or 2.......

 

[Scott Atk]

Are you using the charging wire as part of the kill switch? I ran a 1/0 cable to the starter and a 4 gauge from the starter to the charging lug on the alternator and no problems whatsoever. No need to run the charging wire all the way back.

 

[turbofabricator]

I'm not so sure I'd run welding cable. I can't disagree with your gauge recommendation, although a bit overkill, but welding cable uses many many fine strands to make up the run. While this is great for welding cables (because of the AC component in the current) it's not the best selection for DC wiring.

The reason for fine strand cable for welding is for better flexibility. A solid cable and a flexible cable of equal gauge is capable of carrying the same current. I have not heard the AC vs. DC argument before, though. But then, I'm not an electronics engineer.

I run an 8 ga. wire from the alternator to the starter lug. Then I run a #1 or 0 gauge from starter to batttery in the trunk. I have used both automotive cable and welding cable with both working very well.

 

[Tony Shoaff]

Kill Switch

Are you guys running a kill switch on the back bumper or not? I have to because the car is to fast without one per NHRA rules. I had mine ran like that except the battery wire went to a breaker them out to the starter. I had the alt wire ran to the breaker also but when you shut the kill switch off the car stayed running because it was back feeding through the breaker to the starter.

 

[Bweavy]

Little bit of electrical theory. 12V at 10' of length you have a 10% voltage drop.Every 10' increase the wire by 1 size.
In other words 20' you should increase wire size by 2 sizes.30' 3 sizes etc..

 

[Tony Shoaff]

Factory wire is what size to the alt?

I am running 4 gauge from the alt to battery in the trunk. I did not want to run the wire that far but like I have posted/ only have the time people read. It did not shut the car off when I shut the Safety shut-off switch off?

 

[Scott Atk]

You have an orange wire that connects to your battery in the original location. It powers the ECM. Extend it to the secondary terminals on your kill switch. Works great with no ill effects. If you have FAST, DFI, etc. then disregard.