i really don't see or hear why you would need a silencer. i think my intake made my car louder than the fireball. it's just a nice deep sound. as far as the gasket, i had mine installed so i am unsure <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt='
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