so I was watching a video from the "b is for build" channel on YouTube, and he was talking about how foam filters are much better than gauze or paper filters.
first time I looked at my throttle body after installing my fipk I noticed a ton of oil and gunk from the filter around/ near the plate. before installing the fipk I could have eaten off the throttle plate it was so clean.
I did a bit more research and found the pros of the foam filters much more enticing. it convinced me that I want to switch to a foam filter so I was wondering if anyone has any insight/thoughts on this.

I don't know the opening for the k&n filter diameter either so it's a little hard finding a filter online to replace it with. I think I found 4" but I could be wrong.

tldr: I if anyone has a brand of foam filter that's a direct replacement for the filter on the fipk that would be very helpful to me.