RE: Changing the sound???
It might decrease the air flow from your engine to the exhaust outlet.
Read these to sites CAREFULLY before you even thinking of taking it out again.
[link=http://www.rcuniverse.com/forum/m_5517128/anchors_5517128/mpage_1/key_Guide/anchor/tm.htm#5517128]Nitro Guide and FAQs[/link]
[link=http://www.rcuniverse.com/forum/m_1336488/anchors_1336488/mpage_1/key_Guide/anchor/tm.htm#1336488]A Guide For Beginners[/link]