Breather Filters.....don't do it.

[RedRacer]

Are breather filters really bad? Yes they are. Read further for why.

The honda crankcase breather is a POSITIVE pressure ventilation system.The air from the intake blows into the valve cover. It is NOT a negative pressure ventilation system...it does NOT suck air from the valvecover to the intake.

Breathers remove the source of positive ventilation that repressurizes the POSTIVE CRANKCASE VENTILATION (PCV) valve.

There is less pressure in the crank when you add a breather at the valve cover. The consequence of this is you get more positive blow-by from the combustion chamber past the piston rings and into the crankcase. More blow-by means less cylinder pressure...less cylinder pressure means the burn is slower and less complete...the result is more emissions and less power.

If you want to do this right and remove oil vapor from the circulating crankcase before it goes into the intake valve then, get an oilcatch can and put a breather on the catch can. Then place the catch can in between the valve cover breather and the PCV valve.

Disconnecting the breather tube, which blows fresh intake air into the valve cover, and placing a breather on the valve cover just creates more blow-by and emissions. Eventually you end up with so much blow-by, you will start to lose power.

Don't do this because some tuner moron told you it's a good thing. Don't do this because you want the cool looking little anodized aluminum thing sticking up on your valve cover. Just DON'T do this, period, unless you are going to do it using the catchcan setup.

-- Josh

[crazy93si]

I just didnt do it because I was lazy

[si speed]

I had to do it because the piece on my SRI didn't line up at all with it so I capped the intake off and put the breather there until I can get a catchcan. Let me also mention, the whistling noise it makes at higher RPM's is really annoying too, especially considering it's not a turbie whistling noise.