I had bottomed out a few too many times. A problem when you install lowering springs. I had bent my main support bar on my front air dam. The dealer wanted about $50 for a new one and that is with the discount. My neighbor heated it up for me with his welding torch and we bent it back into shape.
Here is a shot of the front active aero air dam off the car. It is very dirty. It activates at speed so as to let less air underneath the car. Thus reducing drag.