yeah i have enough room lol i have a 10 inch box behind my seat lol with room to spare and those 12s are only 6/4 deep Depth for the drivers is NOT what is required for room. To answer your question you first should post the maximum size box you can fit. And 6.5" deep for a driver + pole vent clearance 1" + MDF front and back 1.5" + excursion clearance 3" = 12" depth, but again that is unimportant as volume/cubic feet determine what you can run. For instance, keeping everything else equal an 8" sub in an optimal box will be louder than the same series of sub in a 12" size in a box that is too small. Install is EVERYTHING and that means building a box that is specific to your drivers. Box first, ALWAYS. ^^^^What ///M5 said!!!!