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Old 10-04-2019, 07:51 PM   #1 (permalink)
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/// 2003 Volkswagen Jetta Station Wagon Roof Rack Delete ///

Hi All,

The headiliner is starting to come down in my 2003 Jetta wagon so I may take it to an upholstery shop to get it fixed and I figure while they have the car apart I may take the opportunity to remove the factory roof rack since I never use it....

Does anybody here have actual results MPG wise from doing this on a similar car (I think my model VW style went from 1999 to about 2008?).

Or barring having the same model of vehicle what are some results (if any) from similar small wagons MPG wise as a result of removing the rood rack?

Thanks in advance for any and all input.

Andrew

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Old 10-13-2019, 08:41 PM   #2 (permalink)
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Ugh...hate roods, especially when they obscure a nicely-designed case.



But back to roof rails: you probably won't improve MPG by a clear or measurable amount. But removing the roof rack will still lower drag; anything sticking out above the body surface like that is responsible for interference drag--i.e. the drag added by the rails and crossbars is more than if they were moving through the air alone. Further, it's almost never the case that the airflow over a car is exactly parallel to the direction of the car's travel, where roof rails would have minimal effect. But any component of the airflow perpendicular to the rails will increase drag (because the sine of the angle of the car's direction relative to the sum of the wind velocity and vehicle velocity vectors is zero when they are the same direction [lateral component == 0] and != 0 when they aren't [ lateral component != 0]--which is most of the time out on the road).

So if you never use them, go ahead and remove them. It can only help.
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Old 10-14-2019, 03:40 PM   #3 (permalink)
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Remember the NASCAR roof fences? Heaven forfend you should ever go sideways, but it might save your life.

Do you want to take that chance?
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Old 10-15-2019, 04:04 PM   #4 (permalink)
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If you don't have any use for the roof rails, taking them out might not be bad at all even if the MPG improvement becomes barely noticeable.

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