Its amazing how a 2 year old thread comes to life again.
Before getting a new air cleaner, try out this calculator
http://www.secondstrike.com/Technica...leanerCalc.asp
Foam cleaners are terrible.
Paper ones are marginal.
The oiled felt ones from K&N, Acell, Fram Air Hog, etc are the best at flowing air by a wide margin.
Also, check the search function for air cleaner. There are other threads.