It doesn't matter. As long as it meets the engine's demands, more cfm equals no change in power output. I had the spec for the factory cai somewhere but, I can't recall it. It was completely sufficient and Ford themselves confirm no need. Supercharger base kits make do with the stock airbox, too, and that's a real engine air demand upgrade.
I remember now... the stock intake flows 748 cfm. Considering we have heads that can flow about 300 a side, that is totally adequate and explains why people don't see gains from a big filter.
Last edited by 5LHO; 03-24-2016 at 08:01 AM.
Reason: Remembered something of some value...maybe.