Dan, Hap & Matt,
       The entire induction air matter, to me, concerns the air flow as it turns 90 degrees to enter the updraft carb/throttle body.  IF the air is in "turbulent flow" there will be a pressure loss in any body thru which it passes..IF the air is in "Laminar flow" the pressure loss will be LESS... The laminar flow condition only migitates this loss.      What Vans A/C data showed was, with a K & N Filter, the flow loss was equivalent with or without the filter in a NA carbureted engine carb..Some other filter brand may do the same or better since this all happened about 1992 and I have had no contact with them since..
       I like the idea of filtering all induction air (Except Carb heat air in my installation) with little or no MP loss, my engine is happier and hopefully will make it to TBO..
      My apologies to all if I wasn't clear in my description and welcome info from those who have more expertise in air dynamics or anything for that matter..  "Old Skeeball"   Don Skeele  850-626-4946
         
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