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My attempt @ more front aero. How can i make these better?

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Old Oct 19, 2010 | 03:12 AM
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Default My attempt @ more front aero. How can i make these better?

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Thoughts/comments/suggestions all welcome

Specifically interested in support and if you guys think this will even hold up. Anyone else have any pictures of how they supported their front spats/canards?
Old Oct 19, 2010 | 03:49 AM
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Doesn't attaching them to the splitter negate any part of the splitter they're covering?
Old Oct 19, 2010 | 06:19 AM
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Originally Posted by curly
Doesn't attaching them to the splitter negate any part of the splitter they're covering?
Splitters work by smoothing out airflow UNDER them, and thus creating higher velocity and lower pressure. You jut them out from the bumper a bit in order to disallow the high pressure air at the very bottom of the bumper from flooding under the car and negating the benefits of the high pressure - same reason why you use endplates on a wing (and why larger endplates are slightly beneficial, to a point). There's a small amount of high-pressure component on top, but the big thing is the vacuum pulled by the increased velocity.
Old Oct 19, 2010 | 07:06 AM
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Gotcha, ignore me then. What's the outside row of brackets for?
Old Oct 19, 2010 | 07:17 AM
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Take a closer look at pic #5.
Old Oct 19, 2010 | 08:08 AM
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I was trying to think of something to do in that same local too... except I have flares that stick out a good 2" too. Looks like it'd work pretty good... in for testing - then copying It sure the hell aint going anywhere with it bolted down like that!

Do you have it such that the front clip pops right off? Saw the buckle and was wondering - not that's sweet.
Old Oct 19, 2010 | 09:41 AM
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Good stuff, you followed John's advice and he's help build aero on a couple cars now for the guy who did the aero on this:
Old Oct 19, 2010 | 11:29 AM
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buy some time in a wind tunnel.
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Old Oct 19, 2010 | 12:34 PM
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Looks good. iirc the biggest effect of the canards is as a tire spat, ie shielding the un-aero tire parts from the wind. If so, you've got it covered pretty well.
Old Oct 19, 2010 | 12:34 PM
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Looks like a good straight forward and proven design. I don't know much about spats, but would it work better if the bottom was closer to the tire? I don't know if the air would be able to come around that and try to hit the tire or if it will do it's job just fine. Again, I know very little and was the only thing I saw.

I really dig the latches holding the bumpe to the fender. I may steal that.
Old Oct 19, 2010 | 01:51 PM
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Originally Posted by rharris19
Looks like a good straight forward and proven design. I don't know much about spats, but would it work better if the bottom was closer to the tire? I don't know if the air would be able to come around that and try to hit the tire or if it will do it's job just fine. Again, I know very little and was the only thing I saw.

I really dig the latches holding the bumpe to the fender. I may steal that.
I'm sticking mine inside the fender and pulling the bumper "back". They also fit under the hood on the factory metal bumper attachment.
Old Oct 19, 2010 | 02:18 PM
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What do you guys think about support, and having them only attached to the bumper via 7-8 bolts on L brackets?
Does the angle look to aggressive?

I am thinking that the design will be "better" than nothing there but i am yet to take a fluid dynamics class so I am just looking at this with common sense.

On a side note, found a fog machine in the garage while digging out Halloween stuff, I wonder if there is some way i can rig up a really really basic wind tunnel to see whats happening to the air on these things.
Old Oct 19, 2010 | 02:31 PM
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i've been under the impression that reasonable angle of attack would be similar to wings - IE: 15* max. perhaps keep < 15* and do 2 or 3 elements like a multi element wing? (by cutting up a cheap ebay aluminum wing).

do you have a smooth airflow under the car? anything which reduces the speed of the air under the car will hurt your aero...
Old Oct 19, 2010 | 02:36 PM
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Originally Posted by jasonb
i've been under the impression that reasonable angle of attack would be similar to wings - IE: 15* max. perhaps keep < 15* and do 2 or 3 elements like a multi element wing? (by cutting up a cheap ebay aluminum wing).

do you have a smooth airflow under the car? anything which reduces the speed of the air under the car will hurt your aero...
Only to the end of the front subframe, some sort of flatbottom is an idea Ive been toying with alot lately. Mike @ GST motorsports and his L gave me a great idea on how to do it.
Old Oct 19, 2010 | 02:37 PM
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Look at the canards in Hustler's pic. I can't tell from your pic if your side fill plate extends up as an upright spat to direct airflow.
Old Oct 19, 2010 | 02:40 PM
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Originally Posted by thesnowboarder
i am yet to take a fluid dynamics class so I am just looking at this with common sense.

On a side note, found a fog machine in the garage while digging out Halloween stuff, I wonder if there is some way i can rig up a really really basic wind tunnel to see whats happening to the air on these things.
1. Fluid dynamics (at least sub-sonic) is pretty much common sense with some math thrown in.

2. Do the fog thing with one of those giant shop fans. It could actually give you some good insights into what is and isn't working. If you can, try and rig up the fog machine to a thin tube so can focus the fog in specific areas the way they do in wind tunnels.
Old Oct 19, 2010 | 03:31 PM
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i was just thinkin.... maybe ask mike if you can use his corner weight scales? put your front tires on them. get yourself a pretty good size fan and watch the scales while changing the AoA. find the angle where you start to get diminishing returns. now you have a range.

then you just need to know your drag penalty to figure where your sweet spot is. to find drag, you could just take the thing up to say 100mph, put the clutch in, and time how long to drop to 70 at various AoA. when your drag goes up but your weight didn't change, you've gone too far.

same thing for the rear wing, just harder to measure if you keep it on the car.
Old Oct 21, 2010 | 04:15 AM
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Decided to build a wind tunnel and test the aero on a few things. Enjoy.

Old Oct 21, 2010 | 07:50 AM
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Sweet video.. the diy wind tunnel looks like it gives some nice results. Your aero work seems to be working very well too. I especially like how that illustrates the airflow coming out of the wheel wells.
Old Oct 21, 2010 | 08:09 AM
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Originally Posted by thesnowboarder
Decided to build a wind tunnel and test the aero on a few things. Enjoy.
Not bad for DIY, that's kinda cool haha.

Is your car still road legal/registered? I'm wondering if you can make a longer probe for that fog machine and have someone drive your car on the highway while you stick the fog machine pipe out the window of another car in the next lane and video tape it. Impress us with that next.



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