I think you have forgotten something about paper filters. I agree with the HRM dyno test, a new paper filter will do *about* as good as a cotton gauze element. But, as David Vizard says, ad 50 miles, and you've already lost power!
I totally back up David Vizard's tests. My dyno tests show the EXACT same differences. I put my dirty paper 14x5 from my truck onto the dyno, and lost 14HP from a used 14x2.5" K&N! I've tested many, many sizes. If somebody says that K&Ns won't add more power, they are miseducated.
To answer other questions:
1. Yes, Summit filters will be just as good as K&N. No difference.
2. Yes, K&N filters will filter as well as a paper unit (papers are a little better). When you look through it and see light, don't let that misguide you. You forgot about the oil in the cotton to trap the small particles.
3. DO NOT use foam filters! They clog up immediately!
I've done alot of research and testing with these things...
1969 Base Camaro
Vortec 355, Perf. RPM, Demon Carb., TH-400
All sheetmetal is NOS GM
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