filters

[Calvin Krug]

Well, it may technically true that a filter with a higher pressure
differential is more effective. In the case of a totally clogged
filter, it's 100% efective, because NOTHING gets through. But, that's
not exactly the point of a filter, is it?   In reality, it's all a
compromise, flow restriction vs filtration ability.  There's really
only one sure way to get more flow without letting more junk through,
and that's to increase the surface area. Big filters flow more than
small ones, given the same type of filter media.  In air filters,
perhaps the "wet' type with an oil-imprednated media will trap more
dirt without creating a lot of restriction simply because the holes
in the filter can be slightly larger, as dirt will STICK to it, and
not just rattle through.  But that's just how I see it.

Calvin Krug
--
  'Work to become, not to acquire.' -- Confucius