Draining battery issue...

[mwatson69_2k]

Well the other day I brought my car to the local Audio Shop to have them tune in my amp... And while they were doing it the battery went dead and they had to jump the car to start it.. He told me that the battery was shot. But they were blasting the stereo to tune it in so with 2 amps of course it is gonna drain the battery. But the guy told me that after about 5 mins of doing this the battery died. So after that I went to autozone and had them check the battery and alternator just in case.... Turns out everything was fine. So I went to class this morning and my girlfriend drove my car to pick me up and she said that she was sitting in the car for about 10-15 mins with just the ACC. on and when I went out to get in the car..I went to start it and it wouldnt turn over.. so I knew the battery died again. She said the radio wasnt cranked or anything and it still drained the battery that fast.

So basically would 2 amps drain the battery that fast? ( and I have a 1.5F Pyramid Cap installed aswell, just not sure if it is a good cap)

These are the 2 amps Im running Alpine MRV-F320 and an Alpine MRD-M501.

So is it just the draw from the 2 amps killing my battery or is there something else I should be looking for....

[tenspeed]

Autozone says the battery and alternator are fine, it must be the sound system. How manys amperes do they draw. Having them turned down won't save you much power. When they're on, they're suckin juice.

[matts]

not to mention that if you didn't charge your battery it's still trying to catch up from that. i'd charge that battery and try it again. and it is possible the system is using juice with the key off.

[mwatson69_2k]

Not sure how many amps they are drawing.. The amps are rated at 550 W RMS and about 100 W RMS at least. Well the battery charges fine. After both times when it died I let the car run for about 10 to 15 mins after so the battery could charge.. I had 2 amps running before but nowhere as near the power as I am running now.. the 550 W RMS amp is what is draining it. SO I guess I am just going to turn off the amp if Im gonna be sitting in the car without it running LOL. The guy at autozone recommended getting a bigger battery. He had a 900 cold cranking amp battery. But how big of a difference would that make.. It will give me more time to run the stereo on ACC but not much right? Then he also recommended possibly to hook up a small deep cycle in the trunk for more stored juice.. But I dont see a point in it.. I understand that it would help but its pointless to me...

And I dont think it is using juice while not on because when I got it jumped the last time I went back home and parked it and it has started ever since...

[AudioFan]

http://www.gaownersclub.com/forum/showthread.php?threadid=32383

heres a link of another post i made. U have a pretty nice system, This might help your power problems and since your going under the hood you might as well upgrade your big three, doesnt take long and is a dream in power issues.

[Bpow]

With the car off and radio on, and two amps hooked up, the battery will definately be drained after about 5 minutes. Thats just the affect of 2 amps sucking everything out and then then alternator can't charge because they car isn't running. If your going to have your stereo on while in your car, I reccomend always having your car running. It sucks for gas but atleast your battery won't die. This should take care of your problem

[tommymcc]

ok, i'll ask a question about my stuff now cuz i don't wanna start a redundant thread

i'm running a deep cycle battery, a 160A alt., 1F cap in the back, 3 amps all rated at 500rms but only two of them are using the cap, they all have the required guage wire going to them, now i had the battery fully charged sat. morning and i was reading a constant 14.4V, now at a local db drag i was competing in street B class so i couldn't run my engine so i was expecting like 12-13V max from the battery, but once i started running my amps for the competition i dropped down to like 10V and the amps cut off in protect mode, wouldn't you think i could get at least 30seconds of good power outta the battery?

so here is my solution, i'm probably gonna put the deepcycle in the back and run only the 2 sub amps off of it, and run a good main battery up front as the main cranking battery and to push the 4 channel amp, do you guys think this would solve the problem?

[matts]

you weren't allowed to keep the car running? that's odd. i would have thought the battery would last longer than that, but i guess not. :???:

[Gimli]

Originally posted by mwatson69_2k
Well the battery charges fine. After both times when it died I let the car run for about 10 to 15 mins after so the battery could charge..

It will take A LOT longer than 10 to 15 minutes of the car running to fully recharge a completely drained battery, especially with these amps drawing so much power from the alternator.

Now if you've drained your battery dry as many times as it looks like you did I'm affraid you just might have killed it. Regular batteries are not designed to be run dry and have very little tolerance to it.

A deep cycle battery (like an Optima Yellow Top) would probably be best for you. CCA (cold cranking amps) will do nothing for you because you need run-down tolerance, not cold cranking amps.

[mwatson69_2k]

what size case would I need for the optima to fit under the hood?

[Gimli]

The 35/75 is the direct drop-in size for 99+ GAs.

[tommymcc]

Originally posted by matts
you weren't allowed to keep the car running? that's odd. i would have thought the battery would last longer than that, but i guess not. :???:

yeah, you can't run the engine in any class lower than super street, the judge told me that ppl were having their stock alt. rebuilt to put out more power and you can't look at it and tell, so the higher up ppl simply said no running the engines that way i doesn't matter what size alt you have


anyways back on the topic, i found the reason the alt wasn't charging, the alt is made to fit a v8 camaro/ta engine, but it just happens to fit on tacomas too, well the idle rpm for a v8 is faster than the idle for a 2.4L, so my alt. was never hitting the speed it needed at idle to replenish the power being used, so when stopped at stoplights or just sat in my truck listening to music it was draining the battery down, so i adjust my idle rpm up to around 1200 rather than 700 and the problem is fixed, now i'm getting around 120A at idle compared to around 30A, we're gonna put a power pully system on it and a smaller spool to bump the power up a little more that way we can turn the idle speed down some, but i'm still gonna drop a 2nd battery in the back for competitions