Quote: our track unfortunately has some stones lifting off the seal on the return road & after seeing 1 racer get a stone flick up from their front wheel & lodge itself into carbs butterflies, i would never ever run without some kind of filtration on my carb. the car with the stone in the butterflies took off with front brakes locked on & plowed into another racecar before the owner could shut it off. not a happy day for 2 racers that day. i'm using Frams Airhogg air cleaner. it's pretty good, virtualy no difference with it on or off, but i now leave it on.
and if you are going to use a "conventional" round style air filter, get one with a breathable top. Just that much more area that is seldom used.
I found the top lid causes issues on flow... you get 2 different air paths that crash into each other and in the end you get less into the carb... I also see that its worse if you have a drop base because the air is going up first then has to turn down to get into the carb.. but the side air is plowing into the lid air ... on the track I dont run a air cleaner
