Common Misconceptions in Aerodynamics: Part 7
Continuing our dissection of the untruths you'll encounter online, today we'll visit the idea that simple "rules of thumb" can be applied to any car for maximum drag reduction.
"Rules of Thumb" are Not Reliable
The claim: Modifying the aerodynamics of your car is as easy as following some simple rules for boat tail angles, diffuser angles, air dam height, and more. Lowest drag is guaranteed if you adhere to these rules.
|An example of testing for optimization. I cut the air dam progressively shorter and measured the change in drag at each height.