Electrical accessory power location

[Zymurgy]

I installed a new positive cable coming off the battery going to the starter and then there is also a positive lead to a block on the firewall, where the fuseable link is located.

Previously I had power cables coming directly from the battery to 2 amplifiers for the stereo. I would like to change the location to the electrical block mounted on the firewall just for a cleaner look. Is there any reason not to use this location?

 

[Big_John]

I installed a new positive cable coming off the battery going to the starter and then there is also a positive lead to a block on the firewall, where the fuseable link is located.

Previously I had power cables coming directly from the battery to 2 amplifiers for the stereo. I would like to change the location to the electrical block mounted on the firewall just for a cleaner look. Is there any reason not to use this location?
View attachment 724115

Depends on if the amplifiers are going to draw more current than the size of the wire running up to the starter relay.

So, if you plan on running a #4 wire to your amplifiers, your wire running up to the starter relay is #12. Not good.

I run mine off the battery stud on the starter. You have #4 wire for the starter. A lot of guys run directly to the battery, but the terminal posts I've seen leave something to be desired as they just screw clamp the wires. You could run a battery cable to a firewall terminal, then tap off it for the starter and amplifiers. That would also let you start with a larger cable, but it's still all dependent on what you need for the amps.

EDIT: Read post #3 and my post #5.

 

[72RoadRunnerGTX]

Still running the stock ammeter-based charging system? Shouldn’t be connecting any running loads at the battery/stater relay or anywhere on the battery side of the ammeter if you don’t want to create problems. All loading needs to be on the alternator side of the ammeter, as are all factory loads, to keep the stock wiring current levels within design limits.

 

[Zymurgy]

Great information guys thanks!

 

[Big_John]

Still running the stock ammeter-based charging system? Shouldn’t be connecting any running loads at the battery/stater relay or anywhere on the battery side of the ammeter if you don’t want to create problems. All loading needs to be on the alternator side of the ammeter, as are all factory loads, to keep the stock wiring current levels within design limits.

I've been trying to wrap my brain around this one.

I thought about it and then kind of remembered seeing a headlight relay video you did. Thinking I needed to see where you got the power for the headlights and I knew you would show both scenarios. I watched that today and I have a better understanding now.

The only thing I need to do is figure out how to run the wiring from the alternator back to the amplifiers. I'm using a #4 wire that powers a 4 channel amp and a powered sub-woofer. I'm using the #4 because I figured out the draw of both and that's what it worked out to. Since I happened to have a roll of #4 wire, that was a bonus.

BTW, I watched your other videos and I just completed the "recall bulkhead bypass" and removed the ammeter bypass I had.



@Zymurgy I need to walk back my suggestion of the starter battery stud.

 

[72RoadRunnerGTX]

I've been trying to wrap my brain around this one.

I thought about it and then kind of remembered seeing a headlight relay video you did. Thinking I needed to see where you got the power for the headlights and I knew you would show both scenarios. I watched that today and I have a better understanding now.

The only thing I need to do is figure out how to run the wiring from the alternator back to the amplifiers. I'm using a #4 wire that powers a 4 channel amp and a powered sub-woofer. I'm using the #4 because I figured out the draw of both and that's what it worked out to. Since I happened to have a roll of #4 wire, that was a bonus.

BTW, I watched your other videos and I just completed the "recall bulkhead bypass" and removed the ammeter bypass I had.



@Zymurgy I need to walk back my suggestion of the starter battery stud.

Yea, when adding loads, load placement matters with this stock ammeter-based charging system. The part 6 video in that series shows how I address connection points for a couple of higher current added trunk mounted audio components. Would caution too, if the alternator output can’t keep up with the added loads on the alternator side of the ammeter while running, power will then be sourced from battery through the ammeter and stock wiring in the other direction (discharge).

For multiple high wattage trunk mounted amplifiers and a mostly stock charging system, may want to consider a separate trunk mounted battery and running an isolator.