how can i make my subwoofers in my truck louder?

[Josh]

I have 2 12" subwoofers in my truck. I have a single cab truck so i can only fit truck boxes back there and they arent very big boxes. I feel like my subs could be louder if i could put them in a bigger box but no other boxes will fit in my truck. what can i do?

 

[draco19]

More subs run in series and a bigger amp

 

[guru]

Buy a fiberglass box paint it the color you want put it in the back and that will make your single cab truck jump like a low rider. 2 12" lots of power in the right box w/the right amp.