18 in SQL sub is it possible

[thericanballer 10+ year member]

Nope. Here is the box, built by kmanian on here:

i wish i could make boxes like that

 

[Biggman44 10+ year member]

yea i know im trying to hit buck up and try to get the dimensions and stuff that box looks amazing. I hope a box like that will still sound good in the trunk or since its going in the trunk will it need to be a different type of ported box? Anybody know where any used good condition sound splitter 18's are or you think the FI Q would be better?