[Steve C.]

According to K&N a larger diameter, short filter will flow more air than a small diameter, tall filter.

K&N formula to determine filter size located here .....
http://www.knfilters.com/filter_facts.htm


Out of interest I have talked with a tech rep at K&N about the air flow requirements for my 505cid engine and if the 'small' 9-inch dia K&N filter assy with X-Stream filter lid that I'm using is adequate. According to their formula a 505 cubic inch engine at 6000 rpm requires about 745 cfm of air flow. According to him the 9-inch assy with the X-Stream lid I'm using will support about 650 cfm. So he said on the street I'm fine. If I went to the track I'd just remove it.

He also supported comments made that the entrance on a Holley 'HP' series carb with it's smooth contour does in fact act like their Stub Stack and will help it work with the X-Stream lid. Whereas apparantly a carb design without a smooth contour (w/ choke tower) and like a Q-jet doesn't work well with a X-Stream lid according to some on these boards.

If interested, previous thread about K&N X-Stream filter lid test on dyno:
http://forums.maxperformanceinc.com/...light=X-stream


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