
I haven't checked volume yet, but I'd say I'm anywhere from 3.5 to 4 cubic feet. I'm running 2 Diamond Audio TDX 104's, powered by a JL 500/1. Diamond states that 1 cubic foot apiece is adequate for these subs, but I've heard a few in enclosures and they definitely like more airspace. So even at the most I'm looking at 2 cubic feet per sub, not including displacement for ports or drivers. Here's the issue. You can look at the sub box, and it's easy enough to see how it mounts in the car. The bottom of every photo is the back of the box (closest to bumper). Diamond calls for 4" ports at 22.5" long tuned at 35hz for a 1 cubic foot enclosure. If I actually run some ports the length of 22.5, the only way in a round port I'd do it is to run it on the bottom of the enclosure, opening up at the front of the box (just behind the back seat.) I wouldn't run them to the back of the box, as the fiberglass is about 2" from the spot where jack used to be. Technically there is approx .5 square foot of space back where the jack is now between the wall of the trunk and the back of the enclosure, however once the box is mounted, that area is almost sealed. It would almost port the enlclosure into a sealed area. Make sense? They might load well, but it wouldn't really be ported. So the thought I'm having is square ported or slot ports. I don't want to fire the ports upward. I could fire 2 ports on each side of the woofer closest to the cabin. The port would open on the sides (3"x 12.25), go inside the box about 7.25" and go down another 7". These are only AVAILABLE measurements and are not what I intend to use, however I have the same available space on either side, so essentially I could use 2 identical ports of this nature. I will also have a trim piece going over the entire enclosure (opening on top for the subs). The trim piece wouln't let much of the port noise into the cabin, however this would help load the subs too. I had intented to port the rear deck somehow too. Let me know your porting thoughts

Here it is with the baffle on.
One thing is the fact that a port that is 22.5" long at that diameter in a 1 cubic foot enclosure might have a tuning frequency of 35hz. You are dealing with a 2 cubic foot enclosure for each sub now so to maintain that tuning frequency the port would have to be 4" in diameter still but only 11" long. So you might get lucky.
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