What are vantage of using...

[Overload]

...the small filter on the engine like this:

<img border="0" src= "http://www.saxperience.com/photos/photo0455.jpg">

[Simo]

There is no real advantage....



One thing... if you have the vent going back into the air induction system you are sending a small amount of oil vapour back through the engine... Using the filter stops this.



However, no performance increase will be seen due to this.



In some respects its better not to use a filter and leave it as standard, as the head breather gases will then be sucked out, as opposed to venting.



The main reason people use them, are because they look good! <img src= "smileys/smiley2.gif">