any catback with piping larger than 2.25 (2.5 might be acceptable, but it's REALLY pushing it) will be LOUD. Not like, "gee, I need to turn my stereo up" loud... I mean, "hey look, the cops are pulling me over" loud. If you REALLY think it's realistic that you'll be adding a turbo, just wait til then, put the $ in savings and earn interest on it.... otherwise you'll be buying a N/A exhaust, and then selling it on ebay or something (but who knows, that might be what you want to do if you don't think you'll be turbo'd for a while)
Hope that helps <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt='

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