Originally Posted by HemiHawk
I think its been proven in the past that something like a K&N filter can improve power numbers, and even throttle response. The problem I've found is the actual filtration they provide. Run a K&N filter for a couple thousand miles then check the tube behind the filter... In my experience it gets pretty dirty. I've run them on several vehicles before I ever checked that. What kind of real world wear/tear would that cause? Not sure, but to me it seems the filter doesn't do what its supposed to do... filter air.
You're absolutely right! Without a filtration comparison this test is worthless. If filtration isn't measured then without ANY filter your hp will go up even more, but then what's the point if you shorten engine life?