Carb or Injection? Makes minor difference, but bottom line is vent from valley cover goes into intake past throttle body (on stock intake manifold, short convoluted tube that attaches between valley cover and bung on intake behind throttle body). This tube is refered to as 'dirty air' side of PCV system. This is also the side of PCV system that some add catch cans to if blowby is an issue.
Vents from rocker covers must go to intake system ahead of throttle body, but behind mass meter (another words between mass meter and throttle body). Can be run seperately or tied together to one vent tube. This is the 'clean air' side of PCV. Reason must go behind mass meter is any airflow through PCV system must be measured air to keep MAF curve correct for fueling calculations. If you open this to atmosphere, or attach ahead of MAF, unmetered air will throw off measurement of airflow - in particular during high vacuum, low load operation (idle with throttle closed). Enough so that fuel trim lean codes can set.
If you are carburated, same idea, just need to have filtered air enter rocker covers, then vent from valley cover to intake below carb. Since this air is not measured through carb, idle mixture adjustments are required to compensate.
Hope this helps.
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