You are talking after removal of the spare right? If so I would say 1 13" w7 if price isnt an option, then power it by a jl 1000/1 amp. It really depends on the music you are listening to. Most high end subs do not need a huge sealed enclosure, 2.5 cubic feet is more like a ported enclosure for most of the subs out there. Quite frankly scratch what I said up there.. If I were you I would get 2 diamond audio 12" m6's. Be sure to seperate the chamber in the fiberglass enclosure, thus giving each sub about 1.25 cubic feet to pounds, and they will pound. I would say power them by a rockford fosgate 1501bd, or you could also power them by the diamond audio 1200.1.

Do you listen to rap?punk?metal?classical? what do you listen to and I can give you a better answer.

 

just curious, why do you want to put it where your spare tire is. I decided when i did mine that i wanted all my stuff removable. i used the space in eighter corner where jack is and the opposite side. you have a ton of room and you don't have to worry about not havin a donut. take a look at my set up. i can remove everything for auto-x's and i still have my spare. nothing is made of fiberglass eigther. my 12's pound!!!!! i went with the jl spec on their website the are 12w0 too. i have a jl amp too. check it out. http://www.cardomain.com/memberpage/538164/3