Question running 2 batteries

[bubbagumper6 5,000+ posts]

So should a 270a alt be plenty of power? Plus a second batt..

Yes that would be more than adequate for running that kind of power.

 

[robbierob02]

Just installed new yellow top optima and still experiencing voltage drop. It has lessened with the new battery being in And my lights don't dim as bad. I haven't been able to get my DMM on it yet to check how low it gets but from the dash gauge it looks to be dropping between 11-12 assuming the gauge is accurate.

 

[Jeffdachef 5,000+ posts]

Basic checklist for better voltages

1/0 Big 3 with solid bare metal grounds _?__

good battery under the hood __V__

add a 2nd battery to the back ____

High output alternator ____

Not sure what size your stock alternator is right now but check to see if its healthy because you shouldn't get that big of a voltage drop with that little power draw.

if your having headlight dimming issues even with voltages above 13.8 it would be better to get a set of HIDs

 

[robbierob02]

Basic checklist for better voltages
1/0 Big 3 with solid bare metal grounds _V__

Big 3 done with 2/0 welding cable

good battery under the hood __V__

add a 2nd battery to the back ____

Haven't added a 2nd yet

High output alternator __V__

Stock 105a alt went out last year so upgraded to 145a alt.

Not sure what size your stock alternator is right now but check to see if its healthy because you shouldn't get that big of a voltage drop with that little power draw.

if your having headlight dimming issues even with voltages above 13.8 it would be better to get a set of HIDs

I have HID headlights and fogs. I notice the dimming in my dash cluster and my taillights

 

[Jeffdachef 5,000+ posts]

I have HID headlights and fogs. I notice the dimming in my dash cluster and my taillights

i suspect something else may be going wrong, within your electrical system because your hardly putting a load on it. what are your voltages reading? get a number reading from resting, one from idle, one from reved up, one with audio on and full blast and let us know

 

[dbjunior 10+ year member]

I'd have the autoparts store do a load test on your alt.

 

[robbierob02]

I went to have the alt tested this morning and it passed. I haven't done the readings from my batt cause I wanted to rule out the alt being bad first. And on my way to the parts store I noticed my voltage wasn't dropping as bad as when I first put in the new batt. Could it have been that the battery wasn't 100% from sitting on the shelf for a while? The date stamped on it was 05/13 so is 6 months enough to make the battery not 100%? Im guessing the alt charged the battery a little bit and now my voltage drop is only happening at idle. I'll post a reading of my voltage with my system loud at idle and see how low it gets.

 

[Slobalt]

You need an alt, I'll be the one to say it. 105 amps to run everything you have isn't enough. I have 140 amp alt and half the stuff you do and my lights dim. When I put subs in I will be adding a new alt, I suggest you do that first before you kill your equipment

 

[robbierob02]

You need an alt, I'll be the one to say it. 105 amps to run everything you have isn't enough. I have 140 amp alt and half the stuff you do and my lights dim. When I put subs in I will be adding a new alt, I suggest you do that first before you kill your equipment

My alt is a 145 amp. The stock was 105 amp and when I was running 2 subs on the stock alt I never had a problem with lights dimming or anything. Once I got the other 2 subs in that's when I started having voltage issues. I'm gonna go back and double check my sub wiring cause I don't remember how I wired the newer subs

 

[Staynlean 10+ year member]

Possibly, what would your new amps be again. I'm not clear.

 

[robbierob02]

**problem solved!** //content.invisioncic.com/y282845/emoticons/veryhappy.gif.fec4fed33b4a1279cf10bdd45a039dae.gif

My dumba** had the subs wired to 1ohm. Rewired them and tested them out and no more voltage drop. Lucky for me I didn't destroy any of my equipment. Next time I'll try to be a little more sober and get it done right the first time