Ok, let me go through the story first...I made a 5.25 cube box for an old orion car sub to use for home theater. I actually designed the box for a shiva on purpose. (anticipating the death of my Orion sub..haha) When I finished, I realized how big this thing really is, and I'm not going to be able to lug that thing to college (95+ lbs). So, I'm cutting off 12" of the top, which brings me down to 3.3 cubes. The port length for a 4" PVC port needs to be 20.XX" long, and my box is only 19" deep. So...is it OK to have a front firing sub, and a downfiring port? If not, I guess I'll put the port on top. Or should I just use this sub in a sealed application? By cutting down the box, The smallest I can get it is 3.25 cubes without any MAJOR modifications. It is running off a PE 300-796, the one with bass boost. (I was a typical stupid 16 year old, and saw the word BASS, so that must mean its better. ), so that's why I'm thinking sealed. If I throw in a TON of extra bracing and extra wood I could cut down the size dramatically, but thats a little far fetched, and I think I'll take my chances with hurting the sub ported. After all, its only 4+ years old. No big loss. Thanks in advance.