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akohekohe
Posts: 111
Joined: Mon Jun 28, 2010 8:36 pm
Location: O'ahu

Will this adversely affect the aerodynamics?

Sat Mar 05, 2011 6:15 pm

For whatever reason the Dealer put this bracket on the undercarriage to hold the inspection stickers. There is no reason to do this except some people don't like the stickers attached to the rear bumper (which is where they are usually put). I think this the bracket messes with the aerodynamics but maybe I don't know what I'm talking about. What do you think?

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DarkStar
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Delivery Date: 25 Mar 2011
Leaf Number: 568
Location: Hillsboro, Oregon, USA
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Re: Will this adversely affect the aerodynamics?

Sat Mar 05, 2011 6:23 pm

akohekohe wrote:For whatever reason the Dealer put this bracket on the undercarriage to hold the inspection stickers. There is no reason to do this except some people don't like the stickers attached to the rear bumper (which is where they are usually put). I think this the bracket messes with the aerodynamics but maybe I don't know what I'm talking about. What do you think?
Hi,

First, please resize your image to a maximum width of about 800 pixels. That will make it a lot easier to see.

To answer your question, any external change to the body will affect the aerodynamics, even a front license plate will do so. The real question is: How much?

I don't think this will affect it any noticeable amount given the other things that affect mileage (wind, driving style, etc) and I wouldn't worry about it. Personally, the sticker has to be there one way or another... I would wonder if it could be moved to the rear window (like in a corner), that way your paint job/bumper isn't affected and isn't on a plate possibly affecting the natural aerodynamics of the car.
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garygid
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Re: Will this adversely affect the aerodynamics?

Sat Mar 05, 2011 9:51 pm

It appears that it would increase the drag, but only a little. Similar to the same sized bracket/object being mounted sticking up from the "roof", mounted near the rear edge of the spoiler.

Putting sticker near the rear license plate would seem better.
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EVDRIVER
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Re: Will this adversely affect the aerodynamics?

Sat Mar 05, 2011 11:39 pm

Don't worry about it is likely insignificant where it is places, besides as it looks you live in Hawaii an last I you likely drive more below 70 than at 70. If it looks good there leave it.

smkettner
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Re: Will this adversely affect the aerodynamics?

Sun Mar 06, 2011 12:01 am

I might put it on a hinge so it would float on the wind. That or slap it on the bumper.
I would be a little miffed if that non oem bracket was installed without a discussion first.
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akohekohe
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Location: O'ahu

Re: Will this adversely affect the aerodynamics?

Sun Mar 06, 2011 1:58 am

smkettner wrote:I might put it on a hinge so it would float on the wind. That or slap it on the bumper.
I would be a little miffed if that non oem bracket was installed without a discussion first.
No, there was no discussion. Yes, I was a bit miffed. I think I'll probably wait a year until the next inspection and have them put the new sticker on bumper and remove the bracket then, but I might mention it next time I'm at the dealer and see if they will replace the sticker now. BTW, the law says the sticker is to be placed on the rear bumper to the right of the license plate.

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akohekohe
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Re: Will this adversely affect the aerodynamics?

Sun Mar 06, 2011 2:11 am

EVDRIVER wrote:Don't worry about it is likely insignificant where it is places, besides as it looks you live in Hawaii an last I you likely drive more below 70 than at 70. If it looks good there leave it.
The highest speed limit in the entire state is 60 mph and that is on a short stretch of H3 and H1 for a total of less than 10 miles.

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Rokeby
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Re: Will this adversely affect the aerodynamics?

Sun Mar 06, 2011 5:58 am

Aerodynamically speaking, that little bracket is a terrible idea.

The LEAF has some of the more complete underbody panel to keep
the underbody airflow moving quickly under the car. The diffuser
at the back plays two important roles. Properly done, and it appears
to have the max effect 10-12 deg angle above the horizontal, it
lifts/directs upward to fill behind the car. It also helps to stabilize
the airflow around the rear wheels.

Airflow around the wheels is anything but smooth and efficient.
All the wheels drag vortexes behind them. The rear wheel vortexes
move all over the place, at times curling under the car almost to the
other wheel. That little bracket is setting up a whole new vortex field
in the worse possible place and causing general mayhem in the airflow.

As for lost MPGs, I'd guess in the 1-3 MPG range, possibly up to 5.

As to placement of the stickers, it would be far better to mount them
on a flat plate lets say fastened to the license plate holder, or
sticky-taped to the back of the license plate itself.

Glenn
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Re: Will this adversely affect the aerodynamics?

Sun Mar 06, 2011 9:38 am

Rokeby wrote:Aerodynamically speaking, that little bracket is a terrible idea.
...
As for lost MPGs, I'd guess in the 1-3 MPG range, possibly up to 5.
??? Gallons of what?

Smidge204
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Re: Will this adversely affect the aerodynamics?

Sun Mar 06, 2011 10:51 am

Glenn wrote:??? Gallons of what?
Blinker fluid, of course! :lol:

Though the "flat plate next to the license plate" is not a bad idea for aesthetic reasons if nothing else. That bracket will add dick-all to the vehicle's Cv.

Find yourself a decent hunk of plastic sheeting. Plexiglass is a bit hard to work with but something like a chunk cut from the lid from one of those plastic storage boxes would be perfect. Cut it the right size and shape to catch the license plate mounting screws and still stick out one side enough to put the stickers on. Drill holes and mount it behind the license plate with the same screws. Bonus points if you can match the car's color.
=Smidge=

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