#TrappingDirt

Dear Sajeev,

I can remember many times where I’d hear, in passing, someone say that K&Ns and other performance air filters were actually bad for my car… daily or otherwise. Their argument was always that the performance filters allowed that 1 percent of dirt to get through. This argument came up again as Engineering Explained did an air filter comparison. His tests showed a small increase in power at a very minor risk of extra dirt (which seems to be less than 1 percent in many cases).

My question is: If an engine is an air pump and you’re filtering the majority of the dirty out, who cares about the 1 percent that gets through and enters the combustion chamber? When was the last time you heard of an engine dying due to dirty air?