maybe i'm just going def. i dunno. but if I try to cruise around with the windows and sunroof open, even with the volume at full power, it still isnt very loud, but is distorion free. can i get it any louder without replacing the HU and amp? it needs to be louder, even if it is at the expense of the sound quality

If it isn't distorting, but won't go any louder, it sounds like you may be restricted due to the power feed to the amp.

In other words, try upgrading the power feed to the amp (get some decent high-current power cable, not the usual automotive 18strand stuff). Also, if you haven't already, upgrade the speaker cable - you'll be loosing shed-loads of power through this. Upgrade you alternator for serious earbashing...

It's a cheap solution. If it doesn't work, then at least you will have done all the groundwork to putting a bigger amp in.