Thanks Danny, now that I've spent most of a hour searching the K&N catalog and web site trying to find CFM ratings 
I've e-mailed k&n tech to see if they'll tell me max cfm for the filters I'm running.
Keith did K&N ever answer ?
I went through some notes and found that both TBS and BDS sell the
5 3/4" X 3" and the BDS tech says flow rate is 414 cfm. TBS says good for 1000 hp, uhmmmm

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