Catch can vent to atmosphere

[crankin]

For those few of you that have vented your catch can to atmosphere I have a question.

Does the PCV not require vacuum from the intake manifold to open the valve?

Venting to atmosphere has no vacuum and thus would allow excess pressure to build. I am just trying to determine the best way to install my can. I really dislike doing things twice.

 

[crankin]

Okay so quick test reveals that the PCV requires vacuum to operate properly because my engine stalled while plugging the intake side of the hose. The intake is providing a very good vacuum source as revealed by how hard it suck onto my finger at idle.

This leads me to believe a vent to atmosphere set up requires gutting of the PCV.

Anyone know how it comes out?

 

[re-rx7]

I'm vta with no problems. Even when I kill into can see fumes/smoke coming from the Pcv.

 

[crankin]

I'm vta with no problems. Even when I kill into can see fumes/smoke coming from the Pcv.

Have you modified your pcv in anyway? Like I said when I plugged the intake vacuum port at idle the car stalled I am assuming because the pcv was now shut at idle with no vacuum applied.

 

[XuperXero]

Also catch can to vta without any issues here. Oil also collects in can, but not as much as others who have can connected to intake.

 

[crankin]

I am still unsure of how you guys are vta without some other modification. If I understand correct you are pcv to catch can with open filter and a have capped the vacuum source at the intake manifold? Without attaching any can at the moment I plug the vacuum source the car stalls.

 

[crankin]

I may be answering most of my own questions by trial and error, so much much for doing things once. Anyways if I cap the intake vacuum while the car is not running then start, it runs and idles fine vta like others above have stated. I guess the car just doesn't like unplugging things while it is running. So vta does work but how effective is it at venting? Instead of fumes being sucked out by vacuum they would have to meet a determined threshold set by the spring tension in the pcv to just expel them. Hmmm, I need to do a little more homework before I decide I am ok with it.

Have you guys running vta noticed any ill effects yet?

 

[XuperXero]

PCV has a check valve built in and should open by itself under its own crankcase pressure. When the car sees boost, it would close it. So VTA should not have ill effects. And it's also pretty obvious that you shouldn't touch anything vacuum related while engine's running unless you're pouring seafoam in or something.

 

[crankin]

I confirmed that the CFM oil cap breather from the Focus will fit and have ordered one. I'll report back my findings with some pics.

 

[re-rx7]

Interesting

 

[BoostBumps]

I confirmed that the CFM oil cap breather from the Focus will fit and have ordered one. I'll report back my findings with some pics.

Definitely keep us posted....

[video=youtube;UvFbmfKPV20]https://www.youtube.com/watch?v=UvFbmfKPV20[/video]

Here is some FoST reviews folks might want to read through...from what I've read you'll want to place a clamp around the filter to prevent oil seep...

http://www.focusst.org/forum/cfm-pe...nce-billet-valve-cover-breather-reviewed.html

 

[JPGC]

I confirmed that the CFM oil cap breather from the Focus will fit and have ordered one. I'll report back my findings with some pics.

Nice find!

 

[MOFiST]

Under vacuum this blocks. So crank case vapors go where if you delete the PCV hose?
*thinking about this the only vacuum would be through the intake. If you put another catch can in line there I reckon this might be a winner. But don't quote me lol.

 

[crankin]

Thanks for the link for those that didn't know what I was talking about. I am going to delete the can all together if the breather works as intended. I am sure the PCV still works to some extent to relief crank case pressure but it is merely a small spring loaded orfice opening to vent as opposed to a larger gravity ball type. Since going VTA I have noticed the foward vent port that returns to the intake (which I have replaced with a filter) is heavily stained leading me to believe the PCV may not be allowing enough room to vent properly and forcing it to vent to the fore most port. What I can say is I have no oil seepage, no blown dipsticks, and aside from the slight smell after a hard pull sitting at the light everything runs fine. Monitoring my ambient and AITs says 3rd & 4th gear pulls I have seen max 20degs hotter than ambient on the stock cooler. I didn't have a base line but seems pretty good to me without that extra hot air, oily crap returning to the intake.

 

[crankin]

Thanks for the link for those that didn't know what I was talking about. I am going to delete the can all together if the breather works as intended. I am sure the PCV still works to some extent to relief crank case pressure but it is merely a small spring loaded orfice opening to vent as opposed to a larger gravity ball type. Since going VTA I have noticed the foward vent port that returns to the intake (which I have replaced with a filter) is heavily stained leading me to believe the PCV may not be allowing enough room to vent properly and forcing it to vent to the fore most port. What I can say is I have no oil seepage, no blown dipsticks, and aside from the slight smell after a hard pull sitting at the light everything runs fine. Monitoring my ambient and AITs says 3rd & 4th gear pulls I have seen max 20degs hotter than ambient on the stock cooler. I didn't have a base line but seems pretty good to me without that extra hot air, oily crap returning to the intake.

edit: BoostBumps I was told by the MFG they stopped including the clamp because ppl where turning the cap off using the filter and damaging the media. No clamp, no turny.

 

[BoostBumps]

edit: BoostBumps I was told by the MFG they stopped including the clamp because ppl where turning the cap off using the filter and damaging the media. No clamp, no turny.

Yes, I saw the manufacturers reply to this in the forum reviews...However, my main concern after going though all of the recent reviews of CFM's breather cap on the FoST forum is that a good number of folks found that these breather caps were actually leaking and in some cases spraying oil out from the filter to the surrounding areas (see pic below)..Still not quite sure after reading all the member's reviews and the manufacturer's response to this specific problem that this was due to a defective CFM breather cap or user installation issues???

http://www.focusst.org/forum/cfm-pe...ve-cover-breather-reviewed-11.html#post724604

 

[crankin]

Yes, I saw the manufacturers reply to this in the forum reviews...However, my main concern after going though all of the recent reviews of CFM's breather cap on the FoST forum is that a good number of folks found that these breather caps were actually leaking and in some cases spraying oil out from the filter to the surrounding areas (see pic below)..Still not quite sure after reading all the member's reviews and the manufacturer's response to this specific problem that this was due to a defective CFM breather cap or user installation issues???

http://www.focusst.org/forum/cfm-pe...ve-cover-breather-reviewed-11.html#post724604

I'll keep my eye on it. Thx for the heads up.

 

[JPGC]

So, I got my CFM breather cap today (I live 2 hours from them...took one day via usps, lol). It fits fine, though close with my STB. I will keep my update here over the next couple weeks on if I develop the same issue described in the FoST forum. Hopefully that was just a bad batch.

 

[MOFiST]

Wow that matches your engine bay color scheme perfect. Nice.

 

[JPGC]

CFM actually called me and asked it I wanted a Race Red vice the powdered red, lol. I was like sure it gives it a nice slightly Ricey touch, lol