alt, batt, or both?

[StrongmanDesigns]

8's don't draw as much power as bigger subs, so you should be fine with just an extra good batt.

[BassMunky]

do both that way if you upgrade later you already have the power

[Jared420]

I have an 06 silverado and I run an audioque 2200 with the big 3 an iraggi 240 amp alt with a yellowtop in addition to my stock battery. I usually rest from 14.6-15 volts and at full tilt I usually drop .3 volts so when I was running 2 2200s strapped i didnt drop below 13.2 and thats with a smaller HO alt and a lower end battery+stock. the alt you have stock in there should be probably 130-140 amps which is a good stock alt I would go with a nice battery first. either replace the stock battery with the better one and add the stock back in somewhere under the hood or get a not huge battery and add it to your stock (obviously do the big 3 either wway)