Correct, but the resultant drag is proportional to referance area.

You gonna take my bet or nitpick?

-b

 

You gonna stop making errors I can nitpick on?

 

CdA is the normal figure given for an automobile. So sorry I left off the A. Anyone smart enough to know that Cd doesn't include A could infer what was meant.

Taking the bet or no?

-b

 

You've even got the color combo I'm looking for.

 

My interior is semi-stripped, I have no softtop, and I have a bar welded in. Plus, the car was in an on-track accident that required $26K in bodyshop work. Maybe not quite the deal you are expecting.

And no, I won't take your bet. I think it's quite possible the peak mpg is around 70 mph or so, but I doubt it is 85. However, it's possible that it could be. I haven't done the controlled testing required to decide for myself.

 

CdA is *not* what we usually talk about in the airplane business, though. I'm an aero engineer, not a auto engineer.

 

So I guess by your sarcasm, you're insinuating that wind direction/speed has nothing to do with gas mileage? Is it so hard to believe that a 15-20mph headwind is going to create more drag on the car than a tailwind? Ever hear of drafting?

 

CdA is number that gets quoted by the car magazine. It's because it's easier to compare between different models of cars that will have very different frontal areas. In aerospace, and for the guy doing the aero on a specific car, the frontal area will remain constant for a given vehicle, and it makes more sense to talk about Cd.

-b

 

That's OK. We might have an even trade:

http://www.flickr.com/photos/ntscblo...7594332684512/

-b

 

No, that's not why.

For an airplane, the ratio of lift to drag is much more important than the scalar quantity of drag by itself.

For a car, that's not true.