no, but not completely no. Look at ur car from the side. See how there are 3 supports from the body to the roof? One between the windshield and drivers window (A pillar), one between the drivers window and quarter panel glass (B pillar) and one bewteen the quarter panel glass and rear windshield (C pillar). Support bars connect these pillars to promote reigidity. heres an example of a c pillar bar http://cgi.ebay.ca/JDM-C-Pillar-Bar...8001661QQihZ016QQcategoryZ33591QQcmdZViewItem
I have a c-pillar bar. I got it off eBay a good while ago. By itself it isn't much, but after adding in other suspension modifications it will show it's worth. A sum greater than it's parts kind of thing.