Voltage experts!! Help!!!

[TurdFergueson2 5,000+ posts]

AC on when you do this?

 

[mazzasec 5,000+ posts]

Have you tried to run additional runs to the back? If your front batt reads higher at full tilt than the back, that tells me that your single run of 0 guage isnt enough, and your losing some current. Do the power wires get warmer to the touch when you crank it? That will tell you something right there.

I have ran 2 runs of positive to the back. Didnt help. Also the wires dont get warm. Could my H/U be the problem? Not putting out enough voltage for the amp?

 

[MmatsDude 10+ year member]

i think the .5 ohms is hurting you .5 ohms draws a lot of power u should test it at a higher ohm and see what happens //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[cx-7heaven 10+ year member]

H/U has nothing to do with your batteries. When you had 2 runs of positive, did you also double up on your ground? It is a loop after all, and if you dont double everything, you still have a choke point( ground).

 

[Andrizzle 10+ year member]

Run two runs of positive from front batt to back. AND two runs of negative from front batt to backs

Then come to us with results.

 

[IDSkoT 5,000+ posts]

You can do all that, but I still say try it at a different resistance.

That amp wasn't designed to be played on .5 ohms of resistance... that's why it's WTFowning your electric system.

Not really WTFowning, but yeah.

Just deal with it... as they said: it doesn't lose any output... so why complain?

 

[JBGabriel 10+ year member]

You can do all that, but I still say try it at a different resistance.
That amp wasn't designed to be played on .5 ohms of resistance... that's why it's WTFowning your electric system.

Not really WTFowning, but yeah.

Just deal with it... as they said: it doesn't lose any output... so why complain?

I disagree. Just because its pulling alot of current and isnt as efficient as it would be at 1 ohm doesnt mean it shouldnt be played at .5. All it means is that you have to throw more wire in the car to transfer the current as said before. You make it sound like more runs of wire dont help when in fact they do. If your losing a volt from front to back you need more wire.

 

[jrwalte 10+ year member]

run two runs of positive AND negative, as was mentioned. That's your best bet to resolve this. You should also try running the negatives to the alt instead of the front battery to see if it helps.

 

[iamamp3pimp 5,000+ posts]

imo, pretty much

best thing an HO alt is gonna do is increase the time needed between charges

when you have a bank of bateries you need to charge them back up from time to time....i need to do mine, maybe ill buy a charger tomorrow

if you put a full charge on the batteries, they will last you longer between charges than if you had a stock alt

so yes, i think that they are a waste.....unless you have enough amps coming from alts they will support your whole system and car, then it is worth it

 

[Joseph M 10+ year member]

ok ok. i have a sd 3k at .5 my self. a red top unfront and two yellows in the rear and i run mine fine. i dont run mine at "full tilt" with jus those two bats cuz jacob told me that 500a of draw but i do, do 3/4 and it goes no lower than 12.4 and i only have a 140 amp with two runs of 1/0. so maybe it is your wire. i have ran it at full tilt with the red, two yellows and a audio force 1100 and the lowest it went was 12.4 so you gota problem with your alt, or wire.

 

[shakinghorizons]

Try disconneting your batts from the others, you may have some bad cells in your batt but they should read all the same if they are connected, I could see I big voltage loss there. Are what they float at with no wires.

 

[iamamp3pimp 5,000+ posts]

thats true

disco them all from eachother and wait an hour

test voltage at each one

front one is gonna be higher because its right by the alt.

 

[DidUHearThat? 10+ year member]

What does your electrical read with the sound system off? What does it read with the sound and engine off?

 

[IDSkoT 5,000+ posts]

I disagree. Just because its pulling alot of current and isnt as efficient as it would be at 1 ohm doesnt mean it shouldnt be played at .5. All it means is that you have to throw more wire in the car to transfer the current as said before. You make it sound like more runs of wire dont help when in fact they do. If your losing a volt from front to back you need more wire.

I never said it shouldn't... it just wasn't designed to go that low.

 

[MECHMAN 10+ year member]

It is obviously not the alternator, as he still has a .8 volt drop from battery to amp, and that is just way too much loss.

Either the batteries are not cabable of discharging fast enough to feed the amplifier, or you need to runs from the batteries to the amp. (which is possible, you just have to "y" the two runs together right before the input to the amp) It should not be viewed as a bottle-neck, becuase resistance of wire is a function of length. If there is only a 2" single thickness of 1/0, and the rest of the length is double, the voltage drop at the amp would be reduced. Furthermore, those dekas have relatively high internal resistance, and their discharge rate isn't fabulous, being as they were designed to be deep cylce. (low amp discharge across a long period of time, rather than a high amp discharge accross a short period) A higher quality audio battery, or a starting battery can physically supply short duration burts of amperage much better than a deep cycle design.

BTW, .5 volt improvement at full tilt is not a waste of money. Supposing that the amp draws 400 amps at full boogie, (which is what that amp should draw at .5ohm) equates to 200 watts better at the subs, plus being higher in the efficiency curve of the amplifier will increase output even more. The stock unit does 65 amps at idle, the Mechman unit does over 150 at idle. That is two and a half times the output, plus the larger case will deal with the heat/load much better that the smaller case stock unit.

Get the current flow problem resolved between the batts and the amp, and you will see even more improvement from adding the HO alternator.