Crankcase breather

[zedron]

There are 6 lines that vent the motor. Two go to the back of the block, two go to front of valve cover, and two to rear of valve cover. When you have a breather you want the venting to be as free as possible because if the motor is pushing more air out though the lines faster than it can escape the breather out the say 1 filter instead of 2 or three, then it will actually start to create a vacuum and pull oil out of the motor into the breather.

The breathers help with excess blow by gas typically found in boosted application or extreme naturally aspirated applications. Typically these gases get routed back into the intake but why would be want to be putting dirty air into our race car? The factory design as well as aftermarket like I have also help remove excess moisture that can build up in the crankcase via blow by as well. The ideal way would be to also create a baffle in the breather that has a line running to the exhaust. This will create a mini vacuum in the breather to help pull gases out the lines into the breather and then out through the filters or get sucked into the line that goes to exhaust to be burned up.