04-05-2014, 03:54 PM
Look at this another way:
The data Red Mist linked to shows a marked difference between the KnN and the Delco; the KnN let in over 17.5x the amount of dirt and the Delco had 1.37x the initial restriction. The data that I linked to shows 1.09x the restriction (I am too tired to calculate percent differences). I would argue that there will be some variation in initial restriction between different vehicles due to the cross sectional area of the filters. Different vehicles have different needs and expected air filter change intervals.
So, IF we NEEDED to increase air flow, an OEM could take a few different routes here:
1) Use the KnN and accept the inferior filtering but gain a bit of extra air flow (we still don't have any numbers to support we have gained any HP or that we needed to!)
2) Use the Delco filtering media but make the filter area twice as large. Now, we have retained the effective filtering and have very low restriction. How do you know that this isn't what Honda has done?
We could double the Delco filter area again to further reduce restriction (competent engineers would match a filter to air flow needs) but nothing we can do to the KnN will improve it's filtering effectiveness.
Interesting video showing sunlight shining through a KnN filter: http://www.youtube.com/watch?v=gNQ6d3ox5Ok
The data Red Mist linked to shows a marked difference between the KnN and the Delco; the KnN let in over 17.5x the amount of dirt and the Delco had 1.37x the initial restriction. The data that I linked to shows 1.09x the restriction (I am too tired to calculate percent differences). I would argue that there will be some variation in initial restriction between different vehicles due to the cross sectional area of the filters. Different vehicles have different needs and expected air filter change intervals.
So, IF we NEEDED to increase air flow, an OEM could take a few different routes here:
1) Use the KnN and accept the inferior filtering but gain a bit of extra air flow (we still don't have any numbers to support we have gained any HP or that we needed to!)
2) Use the Delco filtering media but make the filter area twice as large. Now, we have retained the effective filtering and have very low restriction. How do you know that this isn't what Honda has done?
We could double the Delco filter area again to further reduce restriction (competent engineers would match a filter to air flow needs) but nothing we can do to the KnN will improve it's filtering effectiveness.
Interesting video showing sunlight shining through a KnN filter: http://www.youtube.com/watch?v=gNQ6d3ox5Ok