Gotta admit, that is an impressive record. But no better or worse than any other properly maintained filter should do in those cases.
I'm just curious what benefits (if any) you feel the K&N provide? If there was a significant measurable increase in some performance characteristic of the engine when running a K&N, I could accept that as a performance trade off with filter quality. But the only facts (again, as much as you can believe anything in print [internet, magazine, etc.] is a "fact") I've seen indicate that dyno sheets and track times show no significant improvements in using a K&N on any reasonable motor (possibly excluding high end dragsters and mud bogging, tractor pulling monsters).
And BTW, that was not just "some test on the internet". That makes it sound like a bunch of guys just got together for some comparison testing or something. The test was performed by a respected testing institution, the same type the filter manufacturers like K&N would use if they actually wanted that data documented and verifiable. The accuracy and impartiality of that data is what this company stakes its entire reputation and livelihood on. I'm inclined to put a bit more stock in those results than I would "some internet test".
To me, the only question is relevance. How much benefit do I get from the K&N (or UNI or whatever) vs. paper. What is it's total "cost" (initial, replacements, cleaning, time, etc.)? How much does that extra particulate hurt the engine? How those (admittedly vague) quantities stack up against each other, and how they relate to my overall goals, will determine what I choose. At this moment, this is how I see it.
1) Engine performance enhancement: *No discernable benefit* (hp, torque, mpg, or any other quantifiable metric that I've ever seen tested) one way or the other when applied to my K5, my truggy, or my tow rig, That's a mild "street/torque" motor, a stock TBI motor, and a chipped diesel respectively.
Result: Pretty much even on both counts.
2) Cost: Foam has higher initial cost followed by cleaning/oiling solution costs and time vs. replacement elements. Long term the foam may pull ahead, depending on value of time invested in cleaning and dealing with the mess.
Result: Foam may achieve a slightly lower dollar cost in the long run, but the mess and time offsets that long term benefit for me. I'll lean toward paper here.
3) Engine longevity concerns: I think the tests speak for themselves. Whether you believe the bypass particulate has a major effect on engine longevity or not, the foam filters clearly do bypass more than paper. And that is worth considering.
Result: Paper is the clear winner. How much that matters is debatable.
Based on these results, I can't see any reason to even consider a K&N or anything other than the Delco paper element for *my* uses. I do feel the filtered air intake quality issues are important, which is why the UNI is coming out of my DMax. But it's not so overwhelming that I ran right out and snatched it from the air box before setting it on fire.
I hope you guys don't think I'm on a crusade on this point. It's just something that currently has my attention and interest. I'm really just representing my current views (which do change over time as new data is presented) and trying to gain better understanding with the side bene of also documenting our various views for those in the market for a filter.
Read the data, try to evaluate its accuracy and relevance for your application, and make the best decision you can for your needs. Even then I think you should keep an open mind. In the past, I thought the UNI was right for my DMax, now I've changed my mind, and in the future, I may learn something else that changes my mind back. Is that "wishy washy"? I would say "no". It's keeping an open mind and learning from new information…
