How much vapor is pushed from the Cam cover Vent tubes?

[5ABI VT]

Just wanted to start a thread to see what peoples thoughts or experiences were. I added a catch can to pcv. I planned to run a catch can to each cam cover and remember reading in an old thread there wasn't significant amounts coming from the vent tubes.

I couldn't figure a way to route lines the way I would like so I didn't tackle that when I put it all together. I now have some ideas on how to route the lines to a second catch can and am wondering if its worth using a catch can for each tube or if I can combine the two?

[XfireZ51]

The tubes just vent into the airhorn so not sure how much is being "pushed out" as opposed to being "sucked out". If the cam cover vent material clogs up, it can pressurize the crankcase causing random leaks.

[A26B]

The "normal" flow is from filtered intake air at the air horn to the cam cover via the tubes on each cam cover. The purpose is fresh air purge of crankcase vapors for the PCV system.

At WOT conditions, when crankcase pressure is at its greatest and vacuum to operate the PCV system is at it's least, then crankcase vapors may flow/vent in reverse of the "normal" flow, i.e., from the cam cover to the air horn.

[5ABI VT]

The "normal" flow is from filtered intake air at the air horn to the cam cover via the tubes on each cam cover. The purpose is fresh air purge of crankcase vapors for the PCV system.

At WOT conditions, when crankcase pressure is at its greatest and vacuum to operate the PCV system is at it's least, then crankcase vapors may flow/vent in reverse of the "normal" flow, i.e., from the cam cover to the air horn.


I actually completely forgot this was the source for fresh air back into the system because of the pcv drawing air out :cheers: I will mention on a LOT of photos I google of built LT5s, there always seems to be something altered with the cam covers either to a catch can or elsewhere leading me to think that there is a reason these owners or builders have chosen to do so. I will check my throttle body and plenum after some miles to see if theres any oil inside when i start driving it. If there isnt I may leave it alone and just move to a larger single can for the pcv since I had quite a bit of oil inside for just barely 2-3 hours of driving (alot of wot :) )

Are the cam cover filter/vent material replaceable or accessible with the covers on or do the covers need to come off?

[A26B]

Cam Cover must be removed to replace the "filter" media. FWIW, the intended purpose is to cause oil droplets to coalesce and be retained inside the Cam Cover.