I am planning on doing a sub box located between the 2 front seats. The hardware I plan to use is my CDT QES-1220 in a sealed box (0.7 inc displacement) powered by a ArcAudio KS300.2 (700w).

Is there any downside with this kind of setup? I founded that most people are down firing the subs with this kind of enclosure...

I had this setup in my dakota for a bit, the only downside i found with my design is that I could only get an 8' sub in there.

usually center console sub enclosures are meant to be used in pickups because its a small confined space and an enclosure cant be fit behind the front seats.

i'm not sure what kind of results you'll get with one made in a caravan but it wouldnt hurt to try. downfiring will definatly help with the loading

The downsides that I know of.............. getting the right sub that performs. Two 8" can work really nice though........... and as you're using the ARC amp......... ARC8 8" in a 0.8 cu ft sealed enclosure?? All depends on the amount of room. For the most part, they are not output monsters though.

The other thing in an SQ system that I don't like you can feel the enclosure vibrating if you use it as an arm rest or lean on it with your leg..............unless you build it like a monster so that it's totally dead. But I find that annoying as hell. It takes away from the illusion of where the lower end is coming from in a well setup system. You know it's .......... like RIGHT THERE. That's crap.

Yup, just to test i installed the sub just behind the 2 seats in the center and i definitely know that it's there and the seat/ass is vibrating too much... so i guess ill scrap this idea...

Instead, Ill build a sealed box for my 2 ICON (in the trunk) and see from there, the PTS box I have right now is very good for music but in IASCA comp (track 6) it can't play subsonic ( < 20Hz) without increasing the sub level.