Does this filter have an opening with pleats on the top part? I was looking for a filter with three sides of filter media. I figure it can't hurt. is there an amsoil filter that fits this specs for an I6? I'm just looking for a stock replacement. Currently running a K&N but keep reading how poorly they filter and I'm not exactly racing the TB... so I'm not so worried about the "superior" flow of a K&N.