bill m, those are all legit questions and concerns. i dont fully understand the pc system yet but my NA no longer has a flame trap. i suspect that there is some type of check valve under the intake manifold in the main line from the crankcase to the flame trap that cloggs very easily. i am going to remove the hose from the top of the head under the spark plug cover and start the engine and see if there is any vacuum generated with reving the engine. i know that this hose is connected to the throttle body via the flame trap housing. if a perceptable vacuum is present i think i will assume that all is well and that no significant crankcase pressure will accumulate. this is about the easyest answer to our questions that i can come up with right now, and i may be as wrong as the day is long. mike