Flyby wrote:Senegal that article points to some interesting conclusions. I'll simply say "In God we trust. All others bring data". I'm sure that if you ask of it, K&N will provide testing results that show conclusively that it's filter boosts performance in the Kiz. Should you worry that it also passes more dirt into your engine? To each hos own.
After reading that article, I was concerned enough to cut-and-paste it and sent to KN's support email address. Their response included a link to their own testing site - http://www.knfilters.com/air_filter_testing.htm
After reading discussions on efficiency on that site, I became even more concerned. Promotional info on KN"s main webpage had stated that they did not have to compromise filtering efficiency to get higher air flows, and that they were 99% or better efficient. The link above takes you to a discussion where they say "generally" between 96 and 99%.
The article Senegal posted showed the KN filter had the lowest efficiency in the group (96.8%) with the highest airflow (looks like a major compromise to me). At that efficiency, it was passing dust through at 45 times the rate of the AC Delco ( which had the highest efficiency and not surprising - most resistance to air flow).
I don't know if 45 times the rate for dust is worth a few extra horsepower with the KN. However, not knowing the "brand" of the Kizashi OEM paper filter, it is hard to know what its filter ratings would be compared the the group in the test. A number of other air filters also passed through a good deal of dust.
I responded to KN with the above, and they stated their 100% customer satisfaction policy provides for a refund if not. I am considering doing this (easy - as I purchased directly from them). Just wished I knew more about the OEM original filter - if it was as inefficient as the KN (doubtful), would stay with it until a Delco becomes available.
If you live in an especially dusty area and are looking for long life from the engine, you might want to consider the AC Delco filter if/when they release one for the Kizashi.
Note - would have liked to have know who made the "No Brand" filter in the test. It had over 99% filtering efficiency while having almost as low air flow restriction as KN - that is a good compromise!