thanks guys for your input. but this is what has been rackin my brain for a few days now even when i did try to figure out the formula. and btw i did go to 12volt and i could not find a calculator that measured 2 different depths.

here is the box i want.

NEW CAR AUDIO FORD RANGER EX CAB CUSTOM 2-10 SUB BOX U - eBay (item 400048477485 end time Jun-06-09 18:35:08 PDT)

they give the measurements but not the cubic feet. now here is a box that is locally but has slightely bigger demensions.

FORD RANGER 10" EXTENDED CAB SUBWOOFER SUB SPEAKER BOX - eBay (item 270395359931 end time Jun-21-09 08:27:52 PDT)

now on this box the demensions are slightly smaller and it comes out to 1.26 cubic feet per chamber. the other box has smaller demensions and yet i still keep on coming with bigger footage than the larger one and so are you guys. so how the hell is this happening?!?!? how can a box that is smaller have more cubic footage using the equation you guys give me?!?! lol

in a sealed box my subs recommend .85 cubic feet so i was trying to get as close to that as possible just not under.