Universal Gurney Flap is the perfect additional to any GT Wing or even factory wings such as the ones on the 2017+ Civic Type R, Mitsubishi EVO and Subaru WRX STi. This 3 dimensional rubber piece is 2 meters in length and is easily installed with double sided tape, which is already pre-applied to the bottom side of the flap.
The Gurney Flap (or wickerbill) is a small flat tab projecting from the trailing edge of a wing. Typically it is set at a right angle to the pressure side surface of the airfoil, and projects 1 to 2 percent of the wing chord. This trailing edge device can improve the performance of a simple airfoil to nearly the same level as a complex high-performance design.
The device operates by increasing pressure on the pressure side, decreasing pressure on the suction side, and helping the boundary layer flow stay attached all the way to the trailing edge on the suction side of the airfoil.