One of the hits I got off google said that it's not recommended because the mesh expands in that flow direction, while in a normal configuration it compresses the mesh, allowing it to filter smaller particles.

 google is wrong. Google is correct when looking at foam filters. Concerning foam filters, I agree with google  100 percent.

Please allow me think out loud about googles answer. Seems ok to me for an hour. Then I think the following.



- A "stretched" squared area> in or out, is the same.

-The stretch is the same when lookin at the outside entire filter, and when looking at the folds that comprise it. There for Area is the same, filter is the same.

I repeat the mesh is going to stretch in or out like stated by google but the stretch is the same distance so filter area is the same.

-the folds of the mesh when looked at individually> it would not matter wich way the mesh bows . in or out the bow will be the same.IE The specific dimensions of the mesh will be the same in or out. The filter area does not change only is the orientation of the bow of the mesh changes. Does not affect filter area. Area will be the same in or out when looking at the mesh folds themselves.


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Foam filters blow up and stretch, to open orfices like stated by google.