Voltage drop at idle.

[SentraGuy 0]

I have a feeling this is a pretty common problem that some of you have dealt with. So hopefully you can help me. I have a Fi BL 12 running off a sundown sae1200d. And when I play it at full tilt at idle, I get voltage drop into the 13.0 range (and sometimes even a bit less D:) Although when driving or holding the revs at about 2k, the voltage has no problem sitting at 14. I'm pretty sure this is an alternator issue. But ive heard that even HO alternator have poor output at idle. So what do I do?

FYI- big three is done. And all wiring is in 1/0

Also, I currently have a quote from Excessive Amperage for a 200 amp alt for $385.

Thanks in advance.

[edouble101 314]

You answered your question

[Sir-Lancelot 216]

If its at 13v on full tilt I would not worry about it. Certainly would not throw money st it. That's above your bats resting voltage.

[Impious 1,476]

If its at 13v on full tilt I would not worry about it. Certainly would not throw money at it. That's above your bats resting voltage.

Agreed.

Definitely not worth $400 to try to get another 1V back at idle.

[violence. 0]

reason the voltage is dropping is your alt cannot supply the amps to the batts at idle. bumping at idle never really works well. dropping to 13v is not bad at all. but an alt would be in your best interest. or another battery atleast.

even though that amps small it will pull a good deal of amps. ive clamped those amps at 1500w actual power

[SentraGuy 0]

If its at 13v on full tilt I would not worry about it. Certainly would not throw money st it. That's above your bats resting voltage.

So as long as the voltage stays above 12ish, it won't be causing any serious damage?

[Shogen 325]

nah shouldn't cause trouble, but having better voltage doesn't hurt none either.. I'd probably just look into a second battery if anything, helps a bit and much much cheaper... smaller XS Power or Kinetik would do fine in the area closest to amps...

[Impious 1,476]

The question first needs to be: How often do you sit at idle playing the stereo at full out balls to the wall, and what are your goals for the system?

[Shogen 325]

The question first needs to be: How often do you sit at idle playing the stereo at full out balls to the wall, and what are your goals for the system?

^^ this... I have a hard time resisting the urge for max volume at idle, I do it quite often... Usually when I'm stuck in traffic to or from work which happens pretty much everyday... I haven't addressed my voltage drop yet but I'm looking to get a better alt from DC Power and add a very small Kinetik in the back near the amps for so reserve since I know I can't go easy on the volume when I'm alone in my car..lulz

[jcarter1885 995]

I never play at full tilt when idling, your just asking for trouble especially if you idle to long. But like Impious posted above, it really depends how long you idle at, I wouldnt let my batteries go below 13.0volts but that is just my personal preference.

[Sir-Lancelot 216]

You didnt say what battery, so if it's lead acid if your over 12.4ish or AGM 12.8ish you are not completely discharging the bat, but close to it.

Your system is pretty mild and if it was mine, I would just lower the volume one notch at idle before I bought another bat or alt. It's your money tho. How important is that 1 notch compared to the money to get it back?

[SentraGuy 0]

The question first needs to be: How often do you sit at idle playing the stereo at full out balls to the wall, and what are your goals for the system?

Not much, but it is rather irritating to have to always turn it down for stop signs, red lights, etc.

I have actually looked into XS Power batteries before, I may get more serious about one now. Although I know that wont SOLVE the problem.. Only help.

Thanks for all the help!

[bassahaulic 155]

The question first needs to be: How often do you sit at idle playing the stereo at full out balls to the wall, and what are your goals for the system?

Not much, but it is rather irritating to have to always turn it down for stop signs, red lights, etc.

I have actually looked into XS Power batteries before, I may get more serious about one now. Although I know that wont SOLVE the problem.. Only help.

Thanks for all the help!

You shouldn't be bumping at those locations anyway.

[SentraGuy 0]

The question first needs to be: How often do you sit at idle playing the stereo at full out balls to the wall, and what are your goals for the system?

Not much, but it is rather irritating to have to always turn it down for stop signs, red lights, etc.

I have actually looked into XS Power batteries before, I may get more serious about one now. Although I know that wont SOLVE the problem.. Only help.

Thanks for all the help!

You shouldn't be bumping at those locations anyway.

This is true. And I usually turn it down in the neighborhood/crowded intersections for the reason that I don't want to annoy those around me. But I also live in a city, so there is frequent quick stop and going.

So what do you guys do about the voltage when you're giving friends demos and the car is idling?

[bimmerboy 3]

just give the car a little gas, raise the revs up if your sitting in park/neutral