Test performed by Mario Korf (Occam’s Racer)
Car Tested: NA Miata
Wing Tested: 65″
Test speed: 100 mph, using the following fields:
- Front downforce – This is a negative number, which you can think of as lift. When you add rear downforce (or drag), it lifts the front of the car through leverage, like a see-saw.
- Rear downforce – This is the wing’s job, and varies with wing angle, Gurney flap height, and many other variables.
- Total downforce – Front lift and rear downforce combined.
- Drag – The number of pounds of drag the wing adds. This is a pretty meaningless number on its own, but is used to calculate the L/D ratio.
- HP – An easier way of thinking about drag is how much horsepower it consumes.
- L/D ratio – This is also known as aerodynamic efficiency, and is usually a good way of determining which part is better on the car.
70″ Wing Logic, 12″ square end plates, 3/4″ Gurney
Car tested: Hyundai Veloster N
Changing the smaller end plates for 12″ square end plates added 7.2 lbs of downforce, but also used an additional 1.1 hp in drag. The change in parts returns a L/D ratio of 1.3:1, which means the smaller end plates would be faster anywhere but an autocross course.
Adding a 3/4″ Gurney flap added 48.1 lbs of downforce for 21.4 lbs of drag, which works out to a 2.25 L/D ratio. If you need more rear downforce, adding the larger wicker would be worthwhile on just about any track that isn’t a high speed oval.