Sealed is usually best, unless it is reccommended to put your subs in a ported box. It should say in the box the specs and info on recommended enclosures but i say sealed. You can also look up your subs on the internet and see what the company recommends. Ported boxes seem to not give that much punch but more of a echo'd boom.. lol with sealed you get more of a hit...

 

Exactly right, Jimmz. It's all preference: at least some sub manufacturers include specs for either, dependent on taste. Of course, if you want the best of both, do both and just switch them with banana plugs or something similar. [won't leave much room for anything else in the trunk, tho lol] I have some specs for boxes, sealed/ported, and recommendations for sizes depending on power being fed if anyone's interested.