Hi all,
I would like to better understand blow-by, pcv and catch-can.
I know that some gas and oil vapours will pass piston ring and escape from combustion chamber to crankcase (aka blow-by), and pcv is designed to release crankcase pressure by re-directing blow-by to intake. And catch can is designed to catch the dirty stuff out of pcv so it does not go into the intake.
My car has the spulen v2 catch can. Under normal street driving, the catch can fills up pretty slow (about 50ml for 60km driving). And if I drain the catch can, the stuff coming out are light yellow and gooey. I assume this is normal amount of blow-by that got released from pcv.
But when I go to the track, the catch can fills up super fast. Last track day I drained about a quarter in total (I did about 50 laps of a 3km track). And the stuff coming out are dark, almost black, and not as gooey are the drain from street driving.
My questions are, what is the stuff coming out of the pcv when tracking? Is it blow-by or is it just engine oil? And why there are so much of it? Is it because when corning at high G, engine oil is shaken to the top and get sucked by pcv?
Appreciate if someone who understands this can give me an explanation.
Thank you!
I would like to better understand blow-by, pcv and catch-can.
I know that some gas and oil vapours will pass piston ring and escape from combustion chamber to crankcase (aka blow-by), and pcv is designed to release crankcase pressure by re-directing blow-by to intake. And catch can is designed to catch the dirty stuff out of pcv so it does not go into the intake.
My car has the spulen v2 catch can. Under normal street driving, the catch can fills up pretty slow (about 50ml for 60km driving). And if I drain the catch can, the stuff coming out are light yellow and gooey. I assume this is normal amount of blow-by that got released from pcv.
But when I go to the track, the catch can fills up super fast. Last track day I drained about a quarter in total (I did about 50 laps of a 3km track). And the stuff coming out are dark, almost black, and not as gooey are the drain from street driving.
My questions are, what is the stuff coming out of the pcv when tracking? Is it blow-by or is it just engine oil? And why there are so much of it? Is it because when corning at high G, engine oil is shaken to the top and get sucked by pcv?
Appreciate if someone who understands this can give me an explanation.
Thank you!
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