Anyone have a guess how many CFMs a 4-banger DOHC
flows through the crankcase?
Thanks!
flows through the crankcase?
Thanks!
CFM flow through PCV?
- Thread starter toocrazy2yoo
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not very many.
Not very many....?
It depends on your blowby.
does a new car blowby much? Rings/valve stem seals should be pretty tight, yes? No?
Depends on a whole host of factors. Engine speed, load, wear, ect..
I'd guess 10?
I'd guess 10?
viruoso is right. A PCV is at its sweet spot with mid load, mid vacuum.
High revs with a relatively closed throttle will max it.
There's a fresh air inlet so you don't need blowby to have flow. Blowby will contribute, but how much is anyone's guess.
You could take a plastic bag and put a gallon of air in it, then stick it on your pcv (without melting the bag of course) and seeing how long it takes to suck the air out. Bet it will be under a second or two. Maybe use a trash bag.
High revs with a relatively closed throttle will max it.
There's a fresh air inlet so you don't need blowby to have flow. Blowby will contribute, but how much is anyone's guess.
You could take a plastic bag and put a gallon of air in it, then stick it on your pcv (without melting the bag of course) and seeing how long it takes to suck the air out. Bet it will be under a second or two. Maybe use a trash bag.
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I think it should be a % of your total CFM ..with the butterfly being a "pilot" for it. At idle it's regulated by the rattle thingy ..basically bleeding off vacuum. At higher flow levels where that wouldn't be a factor, I would think that it would have a flow potential just like any other opening ...just like the throttle body. Naturally it's quite a bit smaller then the throttle body's size ..except at idle (where it is regulated by the self regulating vacuum bleed off).
So I say it's at a ratio of total CFM based on the proportion that it relates to the current throttle opening. There are, naturally, conditions and restrictions that apply (length of hose @ HG ..etc...etc....etc) ..but the theory should be sound.
So I say it's at a ratio of total CFM based on the proportion that it relates to the current throttle opening. There are, naturally, conditions and restrictions that apply (length of hose @ HG ..etc...etc....etc) ..but the theory should be sound.
Don't know the flow, but a simple test that I've across is to see if the PCV valve holds a stiff piece of cardboard. I'm using a PCV valve from a 5.0 Mustange in the older Taurus as it passes the card test, but still still flows at a lower rate under lower loads. I was trying to up the 'system' vacuum a bit as the car is long on tooth.
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