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Old 10-08-2008, 09:48 PM   This thread is in the EcoModder Project Library | #1 (permalink)
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Designing/building front wheel skirts v.1.0 (Geo Metro)

Well, after doing the tuft testing video (Video: tuft testing front wheel skirts (Geo Metro) ), I'm definitely sold on the idea of fabricating a set of front wheel skirts for the Flea.

In an ideal world, my next step would have been to head out to my ideal test road to do some A-B-A runs with a set of cardboard and duct tape skirts to get some data on the actual difference I might expect to see. But my cruise control isn't working reliably enough to commit the time to that.

So based on the tufts alone, I'm going to skip ahead to fabrication. This'll likely be the last mod project on the car before cold weather sets in.

Here's what I'm thinking...

Top hinged, like Mike did:




I think this is the best route to take. Attach a hinge to the wheel arch, build a light metal frame that swings from the hinge, and attach the skirt material to the frame.

Thing is, as with my rear skirts, I don't want to drill into metal in a rust prone spot. Fortunately, I had a quick look this evening, and there are already two screws in a good position to use as mounting points:





(No, the tire won't hit the hinge when the suspension compresses - it's offset slightly outward from the side of the tire.)

As for the skirt material, I think I'm going to consider this "version 1.0" and do black coroplast. If they work well, I'll consider building an aesthetically nicer set from fiberglass in the future...

So first step is to make the hinge brackets that will span those two screws...

EDIT: front wheel skirts tested: Tested: front wheel skirts, A-B-A-B

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Old 10-08-2008, 10:21 PM   #2 (permalink)
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You my friend are Aero-crazed. Keep up the good work. Depending on Mileage difference I may do this on mine in future, I am still getting used to the stares from rear skirts.
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Old 10-08-2008, 10:30 PM   #3 (permalink)
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You have to ease into these things. (Unless you're basjoos.)

I remember being pretty self-conscious when I first put the rear wheel skirts on. That went away after a little while. Now, with the rear skirts AND the Kammback, people just mistake the car for a Honda Insight. Seriously - it's happened.

But the front skirts might be more of a hard core aeromod. We'll see what kind of comments they generate...
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Old 10-08-2008, 10:33 PM   #4 (permalink)
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Drink it in, bbjsw10. I live for those looks. Makes me remember I'm a creative, independent thinker... Or is it that i'm cheap?

Just a small detail but I would put those hinges as far apart as possible. Would be nice to make the covers easily removeable.

Can't wait to see what you come up with.
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Old 10-08-2008, 10:37 PM   #5 (permalink)
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Good point, orange. I'll try to get them as close to the mounting points (those screws) as possible for strength.
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Old 10-08-2008, 10:39 PM   #6 (permalink)
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What will fill the gap above the hinge? I would assume coroplast, but then you will need to have a gap between the pieces to allow movement of the lower piece...
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Old 10-08-2008, 10:48 PM   #7 (permalink)
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I was actually hoping to make things so the skirt is one piece, but tilts into the wheel well above the pivot, and out of the well below it.
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Old 10-08-2008, 10:54 PM   #8 (permalink)
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hmmmm.... good idea.

You would still need to have a gap between the metal and the coroplast to allow it to move... you could try adding something along the edge of the wheel well that overlaps over the coroplast? unless you're not OCD on basjoosing.
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Old 10-09-2008, 05:19 AM   #9 (permalink)
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if you could offset the angle of the hinge slightly so than the door hinges forward-upwards, instead of just upwards you may have an aditional aerodynamic benefit, as the air won't be scooped in the open door when the weels are at a more pronounced angle. does that make sense?

perhaps just a few degrees offset form horizontal in the hinges won't present much additional construction problems (just drill the frontal bolt hole as low as possible in the bracket and the rear one higher) but could yield a slightly better aerodynamic configuration when the doors are opening. in addition the airflow will in part force the doors close at speed

just a thought, it won't make or break the design, but when you go as far as makeing front wheelskirts you light consider these little details as well. respect for attempting front wheel skirts anyway!!!
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Old 10-09-2008, 06:46 PM   #10 (permalink)
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[QUOTE=lunarhighway;66147]
in addition the airflow will in part force the doors close at speed

QUOTE]

Brilliant !
So true.

( Also, you plan to have the front lip curve inward into the wheel well ... right ? )

I am curious to see how you get around the problem of having the tires rub against the skirt when you turn the wheel.

I think Basjoos' idea of the conveyer belt wheels is brilliant, but I would be worried that the rubbing would eventually wear into the tires.
I know it won't, but it would if I built it !

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