Someone tell me what they talking about here
Current NASCAR
Johnny, all the nascar cars have a rear block off plate about 4" square in the rear fire wall because they don't run the plate at all tracks. When you are running at a track where you duct cool air to rear brakes you don't need the plate. when at tracks where you need the plate to cover the duct hole there's a plate with 4 sheet metal screws in it to cover the hole and not allow trapped air to escape the car body and help the down force. the rules state what material is allowed and also the plates must be sealed with a gasket or seal material. Aluminum or non steel is not allowed.Its also a safety issue as fire or fuel could come into the driver compartment. Wind tunnel has shown the down force increase to be high enough to gain an advantage.. maybe some trick screws were used to come off late in the race because I don't believe a crew chief would knowingly endanger his driver.. Maybe that's why they dropped the appeal process , just maybe. lol...