If your box is the right size I wouldnt use it. It's called polyfill and is like $2 a bag at Walmart so you can experiment with it

 

Ok so I was at the store and grabbed some polyfill for the heck of it. I was helping my friend with his banshee and noticed a polk sub chilling on the bench. Asked him if he was using it and he said nope! So I decided to try it out in the truck :) stuffed about 3/4 lb of polyfill in the box and put my free polk ex II series in there and WOW. Sounds a million times better than my JL. Go figure lol. Definitely alittle deeper sound but way clearer through the mids.

Guess my new system ran me a whopping $3.49 lol.

Been playing around with it between classes today and used some of the tips you guys gave me also so thanks :)

 

it sounds like you have the basis for a good system man. but id listen to korey and go with the re sr-i 8s. i have the 10s in a downfireing box that i built to spec in my samurai and the subs are magical! they are the most musical subs re makes and will hit the bass your looking for. the 10s hit harder then my 2 15s that i have in my ranger but its only a regular cab so what do u expect