Sup guys. Oh no I didn't mean sealed enclosure, I should have said, separate chambers for each sub instead of sealed. That way one sub wouldn't be missing leaving an enormous port in the side of the thing lol.
Well, I'm going to go copper. I'm going to measure my trunk and see if the 15's will fit. The site says 4.5 per 15, so I need 9cubes. That is a helluva lot of space, even if im walling off my trunk/removing the back seats. If I can't get at least 9 cuft I'll just drop down to 12's. I'm sure 12's in the right space will sound better than 15's starved for room.
BTW, any tuning suggestions? Site says 40hz, but I'm wanting to get some deep lows out of this system this time around.(The ones that you can really feel)