I got 2 old radio speaker(the steel ones)covers. I got them for 5 bucks at a car stereo shop . I drilled a hole in the center and put me a small stud in the hole for the air filter stud and bolted them down. I have a dragster and on the return road the slicks will throw small pebbles and anything else up in the air,sometimes over the front end of the car
I run the Ron's FI Terminators so hopefuly I still get enought air.