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Old 11-19-2014, 02:36 PM   #1 (permalink)
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Roofrails, good or bad?

I have recently removed the roofrails of my car, because they never get used and increase drag. However, on new wagons/estates I'm am noticing a trend.

All of these new cars have roofrails which are closed on the sides.

2014 Ford Mondeo Wagon


2014 Honda Civic Tourer


2014 Peugeot 308 SW


Is this a styling thing of the past, because most people want roofrails on a wagon, or are they actually channeling air across the roof to the rear spoiler in a better way?

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Old 11-19-2014, 02:49 PM   #2 (permalink)
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It's not so much that people think wagons need side rails, as such, it's that wagons are much more likely than other cars to haul cargo. The old style clamp on roofracks are bad for door seals, so having side rails on from the factory is the best way to go. As long as you're stuck having something visible, let the stylists go at it.
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Old 11-19-2014, 02:52 PM   #3 (permalink)
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Many times they do double duty protecting the roof from luggage scratches and covering the roof seam. They're not there to improve aero.
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Old 11-19-2014, 02:56 PM   #4 (permalink)
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I think they also might be serving as drip rails/rain gutters to keep the water from the roof from soaking you when you open the door. I was noticing almost exactly the same sort of step up on the roof of my Tacoma, where the top of the door forms a higher step.

Edit: Not the best picture, but you can see the raised portion on the sides by the doors which is taller than the roof.
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Last edited by aardvarcus; 11-19-2014 at 03:01 PM..
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Old 11-19-2014, 06:58 PM   #5 (permalink)
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Are the rails on those above pictures prepped for cross bars? They look much lower than most side rails and almost look like if they use cross bars that the bars would need a "table" type shape where the cross bars are basically propped up above the side rails in order to keep luggage off the roof. If this is the case, then it looks like the car companies have given the roof rack some much needed attention and come up with a darn good compromise. The rack on my 07 is crazy tall and MetroMPG keeps telling me to delete mine because of the added drag in cross winds specifically. Sure wish I had a nice low profile roof rack for the couple times I'll need one in my life lol
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Old 11-20-2014, 03:49 AM   #6 (permalink)
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Those are longitudinal fences. They are there to kill lift if you get sideways at high speed.

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Old 03-14-2017, 05:40 PM   #7 (permalink)
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Those are longitudinal fences. They are there to kill lift if you get sideways at high speed.
At high speed? Maybe... Yet another reason why ecomodders don't need them.
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Old 03-14-2017, 09:45 PM   #8 (permalink)
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I was making a joke. You don't see the similarity?
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Old 03-15-2017, 03:10 AM   #9 (permalink)
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These newer roof rails seem to have a reasonably aerodynamic profile, quite like deflectors and may have some effect to reduce parasitic drag, in a way similar to the winglets fitted to aircraft.
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Old 03-15-2017, 08:59 AM   #10 (permalink)
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Quote:
Originally Posted by spacemanspif View Post
Are the rails on those above pictures prepped for cross bars?
Yea, it's what they do to get the fleet averages up.

Do what you have to do.

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http://forums.pelicanparts.com/off-t...effective.html

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http://forums.pelicanparts.com/off-t...xperiment.html

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http://ecomodder.com/forum/showthrea...1-a-19525.html
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