open air vehicle vs closed vehicle?

[punchman]

loudness : open air vehicle ie. van & suv VS closed vehicle ie. car

if you would compare the same setup in both of these vehicles, is there big

of a difference in loudness?

cuz i just finish tunning my setup & it is loud as hell. its all entry level equipment just to say. it is in a 93 mazda mpv.

- 2 rockford fosgate punch p1 10" subwoofers

- ported enclosure

- kicker kx200 amplifier

- pioneer ts-a1370r 5-1/4" front speakers

- pioneer deh-p3800mp deck

- stinger amp kit

<IMG SRC="http://photos.friendster.com/photos/04/26/23196240/32557891039510l.jpg">