I am curious if their are any disadvantages to this. I might do it since you dont see it too often but I dont want to sacrafice sound. I believe somone recently mentioned a loss of a fraction of a decibel but I am not so concerned about anything less than a couple db's. I figure it would also increase the volume of the box slightly huh? The box would be ported by the way.
Obviously tho I would rather not hide the best end of the woof inside only to show off an ugly magnet.
I was thinking in my head that since the 'finished' (outside) side of the cone is unobstructed and has the most 'open' surface area this would have some resonance effects or something of that sort depending on which side of the box its facing. Obviously the finished side of the cone is designed to be the side that will be pushing the air. Wouldnt there be a greater effect if you put this most effective side firing into the box? Maybe its a dumb Q but i'm curious now.
there isn't a big difference in output or function, whether you face the sub in or out. i've run subs both ways before and noticed almost nothing different either way.
your concern with the front side of the cone being designed to "push" the air really isn't valid because the rear side also pushes air just like the front. whenever one side pushes, the other pulls, and vice versa.
there's one thing to be concerned with, however: noise. the rear of a sub can be noisy at times because of air rushing in and out of vents and tinsel leads slapping around. usually the noise isn't noticeable, but it depends on the sub, the car, and the location.
you're right, facing the basket out will add to the volume of the enclosure, especially with very small volumes.
most box volumes are calculated with the displacement of the sub (.02 or so) taken into consideration. for example, a .5 cu ft box will actually be slightly larger (maybe .52) to compensate for the volume of the sub. so, when you mount the sub with basket out, not only are you adding in the volume of the cone, but you'll also be giving back the volume where the cone used to be. you'll end up with a .54 cu ft box.