K&N di magpupulbos pag natuyo. Finer filter na foam may possibility pero matagal mga 1 year na tuyo. That happend to my friends car na di ginamit for a year.

as for oil getting sucked in, remember that the breather sa valve cover nakakabit sa intake. kahit paano the engine sucks in oil from the vavle cover. so ok lang yun