Another dry sump question! (crank case vacuum)

[Kwaz-13]

From my obvious posts, no doubt it's clear I'm working on installing a dry sump system. It's a 3-stage deal (that I purchased from a board member :D) and it's being plumbed into a small block that was previously wet-sump. From what I understand, 3-stage systems aren't designed to accommodate excessive crank case vacuum/pressure the same as a system using more stages. And this means that I'll still need to use breathers at the valve covers, but I'm not thrilled about the potential of sucking dirt into the motor.

Is there enough chance of pulling debris in that I should even worry? Say I wanted to fabricate a valve that would only allow a maximum vacuum to occur, while at the same time open fully to release pressure if something (catastrophic) happens. What would the max crankcase vacuum/pressure that I might need to work around?

Any advice is appreciated!

[fast_crew]

You arn't gonna pull enough if any vacuum, (unless it has LARGE suction sections) to worry about sucking dirt in through a breather. Did you have any oil leaks before? You would still want to make sure these are fixed if so. Wrap a rag around the breather and don't look back.