Originally Posted by FE Design

There will be a need to modify and cut the fender liner to allow air to exit.
Our car that gets driven often on the road and tracked often fortunately hasn't seen debris kicked up through the vents.

Closest experience was driving thru a huge pool of water at Laguna Seca and water shot up thru the vents at slow speed. Debris usually has some weight to it and kicks back towards the door than up.