Need help on a new battery
 

Just got my car back from a body shop after getting rear ended. For some reason, my stock battery doesn't have enough juice to start the car. I do have an aftermarket alarm system (Viper) and pretty decent after-market stereo system (upgraded deck, speakers , 10 inch sub with a 5 way amp powering the entire system). Any recommendations on a more powerful battery that can fit in the existing battery tray?

Charge the battery yet? You probably have something not turning off, draining the battery. A stereo and alarm will not make your car take significantly more power to start, unless you start the car with the stereo at full bass blast and it's a monster, monster system. You'll also probably run into the same issue with a larger battery, just a little bit later.

I'm partial to whatever battery is local and cheapest. Just drive down to a local parts store and ask for a battery that has posts of the same type on the same side of the battery but a larger CCA rating. It won't fix your problem unless your battery has gone bad, which it probably hasn't.

Charge the battery overnight, then test to make sure there isn't a draw somewhere. Unhook the positive terminal and run a multimeter set to amps inline of the positive wire and the terminal with everything off. Normal draw should be minimal, less than 0.05 amps. If you're seeing anything higher than that one of the devices you have is either wired incorrectly or malfunctioning. I just bought a beater that had a 2 amp draw from an old alarm the previous owner didn't even know about. This will significantly shorten the life of the battery and the alternator.

If everything checks out, you might need a better battery. I had a camaro with a 1200watt amp back in the day that fried the stock battery pretty quickly. I would recommend getting an optima battery and running lower gauge wire from the alternator to the battery if your system is big enough. I would actually recommend a higher rated alternator as well, but i really doubt that's an option available yet.

Happened to me before and I had the car checked. The guys at the shop told me the alarm system had something wrong with grounding and that my charge was leaking through there. So, for the sake of finding out if it was true, I had the alarm system disabled and lo and behold... I didn't lose my charge anymore.

I'm not saying that this is really your problem but it could happen. Better have your battery and alternator checked though. Usually, that's where the problems are.

stock amp i believe but not 100% sure is 120amps, which is enough for most stereo systems.
how many watts is your amp?
most likely it died because it was sitting for an extended period of time and the aftermarket alarm putting a constant drain.

In Europe , Bosch (Varta) sells this unit as per JIS (Japan Industrial Standard). See dimensions.
I changed my stock one last week as drop down (I have a Sat active alarm). Stock battery is very "light" as power, only 12 V — 48AH (55D23R/L) 390 Ah EN.

The Bosh code battery is
0 092 S40 240 - 60 AH 540 EN

Euro price : Eur 95.00 ($108.00)

I ended up swapping battery to a Diehard Platnium battery from Sears. Car seems to be able to start with ease. After installing battery, I pondered about upgrading grounding wires and possibly looking into a better alternator. Any thoughts about that?

just fyi, very rarely does manufacture matter on batteries, its all about the cca and if you care enough, the reserve. one company cant guarantee their battery lasts longer than another. as far as the alternator goes there is no "better" one they all provide the same amps. neither of these will make your car start better or worse unless they are going bad. this is not a place to splurge because the box claims power gains and easy starts.

the only major difference in battery manufacturers is waranty. pick the best warranty and fnd a battery that meets your cca spec

another tip would be to run a seperate battery (possibly smaller) for all your aftermarket power sources like your alarm and stereo. this saves you the trouble of premature wear on your alt and batt and can guarantee you dont kill your battery if your stereo gets left on you will still be able to start your car.

1) There's only two main manufacturers of car batteries in North America: Exide and Johnson Controls.


2) 99% of the brands you see are made by these two companies.


3) The batteries are built to their specs, so yes, that cheaper battery is actually built worse, that's why it's cheaper!


4) CCA isn't the whole story when it comes to batteries as a very high CCA battery is usually very fragile in construction and sensitive to heat.


5) Alternators need to be physically larger to output more power without losing power at lower shaft speeds (i.e. when idling). If it's not charging at idle, it's not doing you a damn bit of good. Ultimately, if you want your crazy system you need to build your electrical system to handle that in some way (usually adding extra batteries and being smart about turning the system off so everything can charge).