I agree the audio is somewhat lacking. I wish I had external mic. I too get a fair amount of wind noise, especially where its mounted in this video. Although you get an idea what the car sounds like at full song. Hell, you can even here the tire screachin when I point the nose at the wall.
Lone Star Classics 8-6-11 Hallet 130 lap.wmv - YouTube
Now an Indy car on the other hand, doesn't have quite the issue with wind noise
Bernhart's - YouTube
Mat