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Valve cover breather hose v.s. venting to atmosphere with filter?

pelotonracer2

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#1
So, my "old school train of thought" has me thinking about removing the valve cover ventilation breathing tube that re-inserts hot oily air back into the air inlet piping and going with a filter off the valve cover instead. Anyone else try this yet or does this effect something I am unaware of? I know how valve cover ventilation works (and emissions) but I also know that this can make your intake "dirty" and everyone knows lowering intake temps is a good thing too. I've done this on a few different cars and it didn't hurt anything. I can only see positives from doing this mod. Your thoughts? [^]
 


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The only thing I can think of is a question of whether or not that hot oily air aids in lubricating the upper cylander wall and if so, is it any significant amount. I would be interested to find this out as well.
 


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pelotonracer2

pelotonracer2

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Thread Starter #4
The only thing I can think of is a question of whether or not that hot oily air aids in lubricating the upper cylander wall and if so, is it any significant amount. I would be interested to find this out as well.
Highly doubtful as there is little to no oil in the intake as it is. It's more of a PCV emissions thing. I really don't want to use an oil catch can.
 


TheStig

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#5
The only thing I can think of is a question of whether or not that hot oily air aids in lubricating the upper cylander wall and if so, is it any significant amount. I would be interested to find this out as well.
I believe the air is dumped into the intake, so that oil would not be the best thing for your turbo, even in very small amounts.
 


Sekred

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#6
I can't see any real problems with using a filter in the cap and plugging the fresh air hose from the intake tube. Maybe some oil fume smell in the cabin at certain times?, I've heard of people complaining of oil fume smell with vented catch cans that is.
How much oil mist is entering the intake tube anyway. Just so happens I had the tube off my car this morning. I was surprise at how dry the inside of the tube was. Not a trace of oil, I wiped it with paper towel, bone dry. Yesterday I gave the car a good flogging, spending plenty of time on boost so I was expecting to find some oil in the intake tube. If you pull the fresh air hose off the valve cover, there is a baffle and a orifice inside. From the amount of oil I found, it looks like its doing its job ok. My vehicle is stock though, so modding is going stress things more .

Intake tube 1.jpg Intake tube 2.jpg Intake tube 3.jpg
 


rooSTer

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#7
This should work..the Focus guys have been doing this for some time.
 


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pelotonracer2

pelotonracer2

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Yeah, I figure a little cooler air charge couldn't hurt. I'll have to watch IATs and see if there is any difference. I'll use a filter that prevents oil from leaving the valve cover (baffled). I used one on my Focus SVT and there was never any oil splatter or smell, which is good. [:)]
 


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pelotonracer2

pelotonracer2

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I can't see any real problems with using a filter in the cap and plugging the fresh air hose from the intake tube. Maybe some oil fume smell in the cabin at certain times?, I've heard of people complaining of oil fume smell with vented catch cans that is.
How much oil mist is entering the intake tube anyway. Just so happens I had the tube off my car this morning. I was surprise at how dry the inside of the tube was. Not a trace of oil, I wiped it with paper towel, bone dry. Yesterday I gave the car a good flogging, spending plenty of time on boost so I was expecting to find some oil in the intake tube. If you pull the fresh air hose off the valve cover, there is a baffle and a orifice inside. From the amount of oil I found, it looks like its doing its job ok. My vehicle is stock though, so modding is going stress things more .
Yeah that does look pretty clean. Did you run your finger inside the tubing to see if it has an oily film inside? I remember the throttle body on the SVT had oil all in it before I used a filter. I switched to a 65mm TB and port matched the plastic intake to match. Oily film was in there and wet oil inside the TB. Haven't taken my intake off yet to inspect but yours looks really clean. [hihi]

Oh and your paper towels are cute... hehe [burnout]
 


Sekred

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Yeah that does look pretty clean. Did you run your finger inside the tubing to see if it has an oily film inside? I remember the throttle body on the SVT had oil all in it before I used a filter. I switched to a 65mm TB and port matched the plastic intake to match. Oily film was in there and wet oil inside the TB. Haven't taken my intake off yet to inspect but yours looks really clean. [hihi]

Oh and your paper towels are cute... hehe [burnout]
No oily film, I'll be interested to see what yours looks like when you swap out your intake for the FSWERKs.
Paper towels are limited edition to celebrate Australia Day which happens to be today, lol.
 


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pelotonracer2

pelotonracer2

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Thread Starter #11
No oily film, I'll be interested to see what yours looks like when you swap out your intake for the FSWERKs.
Paper towels are limited edition to celebrate Australia Day which happens to be today, lol.
Nice. [:)]
 


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