You provide an awesome explanation of what Line A is doing. I'm just wondering what the benefit of doing that is. For example, why does the catch can need vacuum during boost if the factory system doesn't need it. I get that it there would be no negative pressure to suck air through the can during boost, but why does that matter? The vapors would just be wouldn't be collected until you got out of boost and returned to a vacuum condition, right? You're only under boost for a few seconds at a time, which seems to be fine for the factory system.
As for the CSS, your explanation of what it does makes perfect sense. I'm just wondering whats the point of giving the engine somewhere to pull air from. If it was harmful for an engine to run without one, wouldn't they be common on factory set ups?
Last item that I'm confused about. Line A attaches on the INLET side of the turbo, which raises 2 questions. That air isn't pressurized, so is a check valve needed? Also, since it's creating vacuum from a location BEFORE the turbo doesn't that mean that even if the catch can filters out 90% of the gunk, that means that 10% of it is being sucked into the turbo itself... that doesn't sound good. And it seems so unnecessary since the turbos ingest ZERO of that gunk in a factory set up.
I feel like there has to be some critical info or concept that I don't understand yet.