I build the box, its comes to 2.2 a side for the vmax 12's. But now I need to know where to put the ports!! I build the box so it sits in the truck on the back deck, with the speakers facing the truck and the a$$ end of the box facing the rear seats. This tight fit only leaves about 2 inches from the rear deck of the car. I originally put the ports on top, but then I realized that the ports are going into hole in the rear deck. Will this allow port noise to come into the car? If so, should I move the ports? and where should I put them. I could put the ports in the back of the box b'c I left 6 inches of open space between the rear sets and the box, or I can put them on the front plate of the box next to the speakers. Please let me know which idea is best?
P.S. Where I have the ports now, only 1 inch remains inside the box for the air to get out b/c the box is only 10.5 inches high and the port is 9.2 inches deep.
You could put the ports on the front baffle with the speakers if you want but I think it would be cool to have them vent directly into cabin. The ports play most of the low stuff down around your tuning frequency so having free access with a little reflection gain from your window might yield some impressive low end response.
This is my theory anyways. Jonathan would know for sure.
You could also solve your port length problem this way. If you say you already have a hole(s) in your rear deck just extend the port outside the box till its about a 3/4" above flush with your rear deck. Use some of the leftover MFD to build a baffle to go around the end of the port that would cover up all the ugly "holes" you have except the ones used to couple the actual speaker output in the trunk to the cab. Cover it with carpet(not the port itself of course) or paint it to make it look nice.
You could leave it unbaffeled but you'll get a lil less port output and the effective mass of the collumn of air will decrease slightly resulting in a lil higher tuning frequency. Of course you'll be adding some airspace by moving the port outwards so these two changes will cancel each other out some.
I saw a bandpass box set up this way and it was very cool looking and played very low.
The simplest route would be just to place the ports in the baffle with subs, but I want to hear what Jonathan thinks.