Well I finally took the plunge and ordered a 15" Brahma today. It was a close race between it and the XXX but since XXX's are backordered for at least 2 weeks it made my decision simple. The main reason I considered the XXX was because I own an Xterra and I thought the theme matching would be cool.
At any rate I'm currently designing my box and need some assistance. I am going to run it ported and tuned pretty low. I believe the recommended enclosure is 3-3.5 cubes tuned to 30hz. I definately don't want to go any bigger than this and may even favor the smaller 3.0. I know for a fact Dan Wiggins says the Brahma is NOT a big box woofer and can work in less then 3. I will be running a Tsunami 1100db to it so I don't want to go too big and risk being able to damage the speaker which is why I'm thinking 3 cubes tuned to 30hz might be safer.
So the main problem lies in the fact that even though my Xterra is an SUV, the cargo area is kind of cramped. Due to stadium seating and an overall high floor I don't have much height to work with because I want the box to fit under the factory cargo cover when I'm not in my car. In fact it's so shallow that firing the Brahma backwards is not an option because the dia. is like 15.5" and the bottom of the cargo cover retractible bar is about 14". So I'm looking to do an up firing design which may give me more bass anyways and reduce the risk of something in the trunk damaging the woofer.
Basically what I'm working with is external dimensions of 42" wide(between wheel wells), 13" high and then as shallow as possible to save trunk space. I think the trunk is about 32" or so from trunk lid to seat so if I could do half of that I'd be happy. So 42x13x16 external is my rough guidelines though I'd be willing to extend it another inch or 2 if needbe. I also plan on doubling up the baffle for extra stability and to recess the Brahma so I have a built-in 3/4" gap to make it easier to fabricate a grill. Adire says give 2" clearance to grill. Also because of the high floor I won't gain much space by using the slope of the seat. I plan on using this small area to mount the amps with a little breathing room. I figure if I mount them on the bottom of the box behind the seat they'll be out of view and still be able to breath.
So can somone help with the numbers on getting a box in that space or shallower if possible while tuning to 30hz with a slot port? Also if I aim the woofer up and the port(s) backwards will that cause a problem? I want to install the woofer in the middle of the box so I may do 1 slot port on each side to make it easier and more uniform looking.