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I have been kindly lent a K&N Filter catalogue by a friendly dealer. There are all sorts of neat possibilities available in some of their specialist filters. :bigthumbsup:
I came across an interesting snippet of info from the book: :read:

K&N flow better through their fabric than 'most', but they point out that shape of the filter is important to the net flow achieved.

Large diameter/ low height elements flow BETTER than smaller diameter higher height elements of the SAME surface area!

They then go on to give an very basic equation to work out the MINIMUM surface area of filter you should be looking to put on your motor if you are trying to maximise your HP.

A (surface area sq")= CID x RPM divided by 20839

109 x 7000/ 20839 = 36.61 sq inches of (K&N cloth)..more by a factor of 887/508Â for a clean paper element =63.93sq"!!!!

 Â
 

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Now that is information that you wouldn't find in your everday biker mag, thanks a lot, I will sure keep that in mind when upgrading intake. :bigthumbsup: :bigthumbsup:
I wonder, would the sq." be divided by 2 since there are 2 intakes, 18.3 sq." per side? :dontknow:
 
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