I have read a few threads about oil catch cans and I woul dlike to know if they really work or not and exactly how much oil do they extract? how often do they need to be cleaned out. In all of my years of driving, I have never heard of one of these until i joined this forum and was hoping someone could give a better explanation on this and is the need for one that great? does it improve performance any? or is it just another gimmick??

 

They keep oil vapors from being sucked back into the intake. I haven't personally tried one myself.