I currently have my subs facing forward throught the ski hole but its not completely sealed off from the trunk. (there some space underneath) The problem is that there is too much rattling...cant determine exactly what just yet.
The subs are 2 10's crossed down at 85 hz...

If i built a wall in the trunk and have the subs showing and firing towards the back how would that sound? I know facing the rear is supposed to sound better, but wouldnt you lost spl because the wall is acting as a barrier? What would it sound like if the wall was not completing sealing off the trunk?

How bout when the subs are facing back but the ski hole is not completely sealed off.

How bout when the subs are facing forward, like mine, but with the trunk sealed off?

I wish i could show pics of the type of enclosures i am talking about...I'm trying to aim for sound quality (i.e. upfront bass illusion,) and for the sub to sound good.