I've been using motor savers air filters for years. To me they are the best
air filters on the market. They are very light weight compared to others,you
can adjust the rate of filtration (by using the pre-filter) and the mech screen
helps prevents the filter from clogging(the mech screen shakes dirt off keeping the foam filter clean). On the X-ray type filter once the pre-filter is
clogged it starts to greatly restrict your engine's breathing. I use one motor
savers filter w/o pre-filter for the 5 min heat races and another one with pre-
filter for the 30 min main. You should always rub extra oil on the base and pay
close attention to how the foam the sits in the screen. JE I think Motor
Savers was right, because in your pictures your filter is not really dirty only
the inside of your elbow.