it seems i need to change out my exhaust system from headers to muffler. it currently has a 4-2-1header with a 2" piping straight through. i was considering to upgrade to a 2.5" seeing as the change has to be done but a friend is telling me that i will be robbed of power from my lil sohc zc. so is what he true? will i be robbed of power? is bigger always better? if not why isn't it better? i've always thought that because its bigger exhaust fumes can flow more freely straight out giving you a little more power.