im thinking about pulling my spare and installing a sub there.

 

i have a single 12" sub in my trunk because the bose just did not do it for me. i went from a car where i gutted out the bose and redid everything to a bose system. Just didnt do it for me. My old car i lost all my trunk room and couldnt fit anything in my trunk. this time i wanted bass and i wanted room. I put a single 12" sub into my trunk and mounted my amp at the back of my box and had my box measured out and fit flush to the back wall of my trunk. Looks dope, clean, and have room from my things as well.

 

Got any pictures of that setup? What are the rough dimensions of your box?

 

Take a look at the MTX slim woofers. If you get 2 10" woofers you should be good. They have very good response and will give you the extra bass you are looking for, with next to no space loss. You will get a different opinion from everyone on this site so go with something you like.