sub box orientation...

most people who get subs buy the box and mount them facing the rear of the car. i have used both ported and sealed like that. i know that in my 93 accord if i flip the subs to face foward then the bass is pretty much gone with the trunk closed. now i would like to know if anyone has had any luck with another orientation? like downward or upward. i have seen people mount subs upward but only in pics and i have never heard them. currently i have 2 audiobahn natural excursion subs hooked in a 2ohm configuration attatched to an audiobahn A8000t amp in a ported box. any ideas to help get better sound or more bass?

I've tried facing forward, back and up. From my personal experience I get the most and best sounding bass when I have the subs facing the rear. Facing forward it sounds muffled and facing up they sounded hollow.