The stock one fails and causes check engine lights to go off b/c it is a ribbed design, its really bad for airflow and also it cranks and causes havoc. You'd be foolish not to buy one and prevent that from happening to you. this + K&N will give you about 5HP, not a huge amount, but its better than nothing.
You obviously aren't very knowledgable since you are insulting the best oil out there.
children.
