sub enclosure for 02 mustang gt

Ported for kicker is the way to go for a rap guy/ bass head. You will get a lot more output. Just with it peaking in a more narrow freq range.  But in a sealed box you will have more SQ because it is a flatter response through the frequency range. CVR like the L5/L7s also like airspace. The closer you can get to the big end of the box range the more output you are going to get from the sub. The mustang is a tricky one to design an encloser for as said above. I actully did  a box for 2 15s bandpassed in one before. It had to be completely built inside the trunk but, it can be done. 1 12 should be pretty straight forward and not that bad to do. Just take lots of measurments. to make sure you can get it in the trunk.  Sealed is definately better for a first time/ novice builder. Ported boxes are pretty picky. There air space along with port has to be spot on or it will not sound right.  But back to your question. Sealed is going to be your best bet. Space will limit your cubic foot for the box but i would try to get as close to the max box spec as possible. That will be your loudest config for SQ and output. Also from my experiece they seem to work better in seperate chambers but this will also come down to space limitations. It could actually be better in a shared chamber if say you can only get a 3 cube box or less for the pair.

The best advice i can give is take as good measument as you can of what will fit in the car. and then play with the box calculator on the site to get the box as close to the most air space  possible within the max specs. As for building the box Kicker has now addded a box building section to there web site in the support tab to help you with the actual construction and there are a few threads and tutorials here as well that should really help you get started. Good luck and if you have any further questions. Feel free to ask.

1.5 per will be fine. Seperate chambers may not yield as good a result as one chamber.  As far as output But, with seperate chambers if the dreaded happens that you blow one sub it can really help to save the other.  Kicker actually also recommends seperate chambers when at all possible. As for sound make sure the box is fully air tight. It should produce well with good clean power and SQ should be pretty good with correct amp tuning.

As for driver displacement Kicker specs include the driver displacement already. Other than airspace the only thing needed  for there recommended spec boxes would be figuring and adding port area which does not apply to you building a sealed box. 

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