sixto after reading your response it's clear my question wasn't clear.
The question should have been, "If crankcase vapors are vented / exhausted through the breather pipe, how does fresh air enter the crankcase".
As for mixing crankcase vapors with fresh air before the intake, I'm OK with that (provided any oil has been removed first). For me the last thing I want is my car to create a smelly atmosphere at idle - some of us remember cars from the pre PVC era
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