I recently changed my air filters and noticed there was a letterbox opening underneath the car for the air to draw into for the airboxes.

I am curious why a flap or similar was not developed to allow more volume of air to be captured and directed inside the letterbox envelope?

I am tempted to take my undertray off and take it to a welder to put on a small flap panel at 45 degree that extends maybe half an inch.

See pic (ps thanks VantageV8.com great site!)

 

drag..

 

maybe it will produce lift?

 

Yes lift and drag could be an issue... Nothing like getting induction from the front of the car I guess.

 

Air to the airboxes comes in through a central snorkle behind the grille and in front of the radiator. The slot in the undertray is to vent hot radiator under the car.

 

Ahhh right ok. I was looking at the pipework from the letterbox and it appeared to be directed into the airboxes.