hi,
its ron here.
for the HKS filter, which i do have.
the best way to clean is with degreaser. do a couple of times orso
then leave til dry. oil it with air filter oil, can be found at motor shops.
these filter are pretty much the best on the market so you dont need to replace them.
i dont oil mine and found that topend power is greater, also build a cold air box for best results. and if you have a front mount, feed the air through the hole where the old pipe goes.
hope this is useful
regards
ron