Ok so here is the deal. For quite sometime now ive been running my 12" DP in a 1.5 cu. ft. sealed box. It does fine and sounds really good with my BX2005D on it but im looking for some more low end extension. So I did some measuring and number crunching and I have room on either side of the box in my hatch to run possibly dual 4" pvc ports but ive decided to use only 1 port to keep port routing well hidden and under 20" long. All the pipe will be external as well so air space inside the box will not be altered. Anyone got any opinions? Im thinking I can get by with less than twenty bux total for materials to add some good low end extension. Oh yea and this will be in a camaro as well so I aready have premium conditions for the most sound possible.