For some time I have installed K&N type air filters to diesel engines of many types because the blow by fumes carry oil mist and prematurely oil up paper filters and restrict air flow to the point of filter element collapse.
Having said that...I understand blow by is a symptom of the amount of wear and ideally the engine should be rebuilt or exchanged. This is not often in the customers budget.
So, in order for this to reduce the impact on a paper filter....I have installed oiled filters. Engine still has blow by but oiled filters can handle this.
Now...looking into the filtering ability of air filters I have stumbled across this :
K&N Air Filter Review - Debunking the Myths (and why OEM is better)
It appears all is not as advertised....surprise, surprise. ...but I didn't expect such a damming test result.
Your comments ?.
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