helping set up my system
 

i got a ford ranger with a pioneer 6800 deck, kenwood 900watt rms amp, stock speakers and a 12 inch dual voice coil digital disign sub. in a ported bass works box, i was wanting to get it tuned in just right for the best quality. could someone help me out please

If it's tuning you want, you should ditch the bassworx and build your own ported box based on how you want your bass to sound. If you're looking for SQ, then tune it nice and low.

what is sq? im a newbie, i just want it to be loud and sound good

SQ stands for sound quality. What model is that DD sub you've got? I'd guess a box say 2.5 cubic feet tuned to 35hz would meet your needs. Maybe somebody who runs DD can give a solid recommendation.

Get rid of the Bassworx candy box and get one that is purpose built for that sub. It will come alive and try and eat you when you do. Next you are 100% for sure going to need a amp on the other speakers (and preferably new speakers) so that you can actually listen to your music while the bass from your sub is slamming your ears past your face.