I just got a Lid for my Camaro SS and want to replace the stock air filter too, what is the best air filter performance wise, I thought it was the K&N but other people tell me it's not.

 

Performance wise (as in more HP) then you want a stock AC Delco.
Paper outflows all others. It will be replaced more often and hence be cleaner more often. It will cost more as in you will have to replace it, but if you are paying 20 for each, then its only after you have replaced it 3 times that you are paying more than a reuseable filter.



Than being said..
Filtration wise (as in less HP but less particles get in your motor)
look into
K&N - Redish cotton filter media
Holley - Blueish cotton filter media
Accel - Yellow? cotton filter media
Amsoil - Black foam

All of the above are reuseable with the Amsoil filter offering the cheapest cost of ownership.


My sig leads to pages with dyno runs and whatnot that were preformed on the same day to illustrate my findings.

 

Does anyone know what auto parts stores sell the Holley Pro line filter?

 

As far as trapping contaminents goes, I think the Fram CA3914 is pretty good.

Every time I check or change my filter, there's always dirt particles, bugs, etc. at the bottom of the airbox that never made it through the filter.