A big thanks to anyone who can figure this out for me, your time is greatly appreciated.

I currently have a JL 13.5 W7 subwoofer installed in a custom ported box in my G35. It is great, but it does not live up to it's full potential. I am a dummy with the measurements and don't think I will reach a 100% accurate conclusion, so I was hoping to find some help here.

Is there ANY way possible to get the RECOMMENDED SPEC ported box into the trunk of the G35 coupe? It could involve removing the back seat barriers/speakers below the back window or possibly lowering what is under the spare tire? (no idea). The spare has already been removed obviously. My local sound place told me it's not possible to get the box into the trunk. I figured I'd give it a shot. I love this car, I don't want a new one. But, I want my music the way it once was.

Here's the measurements of the recommended spec box along with some notes from JL.

Wall Thickness 0.75 in / 19 mm
Front Baffle Thickness 1.0 in / 25 mm
Volume (net int.) 2.375 cu ft / 67.3 L
External Width (W) 22.25 in / 641 mm
External Height (H) 17.25 in / 438 mm
External Depth (D) 16.25 in / 419 mm

Enclosure Notes
Net volumes given above do not include the air volume displaced by the speaker (Driver Displacement). This value must be added to the net volume along with the displacement of any braces and/or ports (if applicable) to arrive at a gross internal volume. Air inside a port is not part of the effective net volume. Calculate ports as solid, not hollow objects.
* The W7’s employ a pole vent to remove heat and pressure from the inside of the speaker.This vent is located around the JL Audio badge at the rear of the speaker. A minimum distance of 0.75 in (19 mm) is required between the back of the speaker and any wall of the enclosure to allow proper operation of the pole vent.
The dimensions given for the enclosure examples above take all applicable displacements into consideration


Once again, thank you very much if anyone has any suggestions on how to get this box in the trunk or an answer to this.

 

Making a rectangular solid out of wood, it'd be pretty difficult to do it, but somebody good with fiberglass could easily do it.

 

Difficult, but possible you're saying? Would the wood have to be built INSIDE the trunk? Or is there a way the box can be built and then placed inside somehow.

 

It's difficult to the point that "if you have to ask".

There's enough volume in there for the ported box. You'd almost certainly have to assemble it inside the trunk unless you want to give up almost all the space. Overbuilding the box to fill even more space than necessary, then taking away volume inside would be the way to go. Just pretty much write off half the trunk space and go for it. Check this thread for inspiration:
https://g35driver.com/forums/audio-v...m-gallery.html