Actually be responsible for the environment don't do this. Remember we all have to chip in to take care of the air we breath. Yes you can say that I'm only one person and that's all. But if one person does it, another and another it adds up to alot of noxious fumes. And considering you live in WA anyone east of you will breath in those noxious gases.

Plus federal regulations say you cannot mess with emissions equipment that come stock on a car. If you are caught there can be some stiff penalties and possibly jail time.