I have finished working on my second subwoofer box, this time being 5.8 cubic feet ported at 36hz. It is separated into 2 boxes, to ease transportation when removing them from the trunk (a single box would have been a back breaker!). It’s pretty damn loud, but I should have made the extension lower (32hz perhaps). I will be putting in-trunk shots in the future when I get the chance.
Pictures: