redkysolarase wrote:My oem battery got in it's last kick there about half a year ago and I went with a cheapo Wal-mart battery (yeah I know bad mistake but I didn't have much money at the time). Well it was all find and dandy until here about a few weeks ago and now my lights dim sometimes when the bass hits.. What do you guys think I should do get a new battery or just a better altenator(sp??) and if battery yellow or red top? Btw I have two 12's with a 500 watt amp. so I know it's sucking up some power.
You will need either a deep cycle battery (such as the yellow top), a capacitor, or an alternator that puts out more amps. Since your not drawing too much over the limit, I think any of these will do. A better alternator would be the best solution if you want future upgradability of anything electrical.
And neither an alternator or battery will offer better performance. Battery's main job is to start the car and keep the voltage constant. Alternator is to provide enough juice to power the car and all the stuff in it. Battery's secondary job is to "back up" the alternator if you go over its limits, but only deep cycle batteries are really built for this secondary purpose. Any battery will offer some juice up when the alternators overtaxed, but unless its deep cycle, it wont do it too well.
Red tops are built to start as reliably as possible and last a long time. THe yellow top, and other deep cycle batteries, gives some of this up to be able to offer up more juice during normal operation (or ability to cycle deeper than just typical starting)