After 40mph its great

. Its restrictive over an open filter. I had both sides om my car. Dont drive it in a heavy Florida rain either. I had the right side blowing air on the turbo. It does pull air from front of car but not as much as a open filter. I took the canister off and just left the the hose blowing on the filter. I going to put them back on when car is finished because I like the way the look. Doing a test would consist of scoping tps and maf with and without canister installed. Without will flow more air . But its warm air

. Maybe a little less and cold would be better

. Thats all Im saying is two reputable buick shops told me to remove the canister so I did