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Old 09-29-2010, 08:58 PM   #5 (permalink)
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One thing to consider Otto is interference drag. Two bodies near each other act like one large body. Sometimes a large smooth blended fairing between, in this case, the side of the car and the mirror body, can have less drag than a narrow stalk no matter how aero.

Likewise having a mirror that has the glass face in the convergent area can act as a kamm surface. In effect having a larger mirror fairing and a fairing that is molded into the body might be an advantage.

I agree that some mirrors are pretty oversized. Many have conveniences of remote adjustment and heated. Kind of hard to give up. Hope that you can prove that your motorcycle or race car mirrors are effective on our Tanks.
6% or higher is fairly significant. I will be glad to learn.



Quote:
Originally Posted by Otto View Post
Thanks for the links and thoughts. I've read probably on this website that outside mirrors may be ~6% of total drag, but if mine are way bigger and draggier than need be, and I can find suitably large enough motorcycle aero mirrors for cheap, why not?

Elsewhere I read that Indy and Formula 1 cars pretty much had been bolting on whatever mirrors were lying around, until recently somebody took another look at this drag source, with good results.

I may find a cheap eBay or similar set of aero mirrors, and make stalks out of aero tubing of teardrop cross-section, or keep the stock round stalks but add teardrop fairings to them. These are only ~1/2" diameter stalks and hold the mirrors in place at 100+ mph, so I am mystified why the car manufacturers use such thick, draggy stalks, not to mention crappy oversized mirror housings.
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