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Old 02-20-2013, 02:27 PM   #1 (permalink)
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roof cargo box rearward facing?

Hi,
every time I see someone with roof box I wonder: wouldn't be better from aero point of view to mount them rearward? They usually have pointy front, but blunt back... example here.


Did anybody coast down test? Only info I have found so far is in this post http://ecomodder.com/forum/showthrea...enalty-96.html

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Old 02-20-2013, 03:16 PM   #2 (permalink)
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Interesting idea... I have a cargo box (but no roof rack for now ) so maybe I'll make some tests someday.
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Old 02-20-2013, 03:21 PM   #3 (permalink)
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I have thought the same thing. Haven't tried a coast-down yet. I use it for skis and snowboards in the winter only. Perhaps I will try it before I hang it up for the summer.
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Old 02-20-2013, 06:15 PM   #4 (permalink)
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Build a blunt fiberglass "front" onto it and you'll be good to go. Probably not that much difference, though. 5%?
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Old 02-20-2013, 06:31 PM   #5 (permalink)
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facing/stability

I don't 'know' anything about these cargo carriers.
As an independent entity,they are aerodynamically 'backwards' as far as 'ideal' drag goes,so you make the leap,that they should be reverse-mounted.
The only caveat that I can think of,is that during wind tunnel testing,with yaw introduced to simulate some crosswind,that they went with the rearward center of pressure of the blunt rear as a concession to straight-line stability.
My opinion is to never use any of them,using a receiver-hitch mounted cargo carrier instead.Preferably boat-tailed.
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Old 02-21-2013, 01:13 AM   #6 (permalink)
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Quote:
Originally Posted by seifrob View Post
Only info I have found so far is in this post http://ecomodder.com/forum/showthrea...enalty-96.html
Try these:
Which way would you install skibox
Most aerodynamic cargo box?

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[Old] Piwoslaw's Peugeot 307sw modding thread
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