Custom rear spoiler for the Missile

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Yes 500, the mechanism is from a Crossfire.
72, Since Im running a completely digital dash, Ive contacted the manufacturer to see if there is a way to get the information from the spedo.
Andrew
My bad. should have read the whole thing instead of skimming and looking at the pics. Kinda like the way I read Playboy when I was younger.
 
from the angles I can see.. It doesn't look like you will get much aero benefit at all unless you seal the bottom or change the angle so it just tips the back and makes a spoiler rather than a wing out of it. Or, you could make it stand up slightly more, and use it as an airbrake, Mercedes Slr Mclaren uses one, so does the Bugatti. See:

[ame="http://www.youtube.com/watch?v=myovuS2vihM"]YouTube - bugatti veyron air brake[/ame]

[ame="http://www.youtube.com/watch?v=mvfG_jEXosw"]YouTube - 2010 Mustang functional rear air brake spoiler by Classic Design Concepts[/ame]

[ame="http://www.youtube.com/watch?v=u7Vb2sIzR9I"]YouTube - SLR Air Brake[/ame]

And a brake pressure switch would be a whole lot simpler than a speed switch. though I would do am manual override switch so you could turn it on or off. It would then be actually helping something rather than just for looks.
 
The effects a wing has on a car can only be determined by actual testing. All cars have different aerodynamic properties. More modern cars all tend to have the general "semi-teardrop" shape, so their aerodynamic properties are very similar.

When Chrysler wind tunnel tested the Superbird and Daytona Charger, they went through many wing, nose, and air dam configurations. The wing they ended up using began to provide downforce only at about 60 m.p.h. and the AOA was adjustable. However, the greatest secret of the wing assembly was the lateral directional stability it provided at speed. Everybody else concentrated on the wing itself and not on the vertical stabilizers.

I can't wait to see your results, Andrew.
 
The effects a wing has on a car can only be determined by actual testing. All cars have different aerodynamic properties. More modern cars all tend to have the general "semi-teardrop" shape, so their aerodynamic properties are very similar.

When Chrysler wind tunnel tested the Superbird and Daytona Charger, they went through many wing, nose, and air dam configurations. The wing they ended up using began to provide downforce only at about 60 m.p.h. and the AOA was adjustable. However, the greatest secret of the wing assembly was the lateral directional stability it provided at speed. Everybody else concentrated on the wing itself and not on the vertical stabilizers.

I can't wait to see your results, Andrew.

Yeah don't tell all the ricers with their Civics, but most of the wings/spoilers on cars these days are too small to do much of anything. Even the larger ones don't usually have any effects below 60 mph.

Evidence of that can be seen by looking at that Superbird wing. Its huge! The problem with the design of the Dart (similar issue with the Charger) is that the profile of the greenhouse drops off so quickly. By having a tall, square greenhouse, you block a lot of air. And in the wind tunnel, you'll see separation of the air flow at the back of the roof. I'd bet the Dart is actually worse, especially the '70 up version, since the decklid is shorter than on a Charger. The wing would likely have to be taller. Modern cars have more of a "tear drop" shape so that the air flow remains laminar, and attached to the car, so you actually have a significant amount of air flow across the trunk. Which is why the wing on the Superbird had to be so tall, it had to be that way to get it back into the air stream. On a modern car, you can have a shorter wing or spoiler, since its still in the air stream.

Take a look at an 2003-2005 SRT4 (the neon based version). They had a pretty large wing from the factory, and one that was claimed by Dodge to be functional. On one of the forums I used to be on a guy bought an SRT4 wing and put it on his Neon, which originally just had a small spoiler. He immediately noticed a rattling noise at speeds starting around 60 mph. It turned out that at 60 mph, the wing created enough downforce to cause his trunk latch to rattle. That was it.

So, as far as making this modification "functional", I'd have to be a little skeptical. It has a pretty decent surface area, so it might actually work a little. But the effects would be minimal at best. And, as fishbreath pointed out, you'd actually have to put it in a wind tunnel to know if it was even a positive effect. It would be pretty easy for it to produce a significant amount of drag, without producing any downforce, and all that would do is lower your MPG's. Even downforce really isn't helpful unless you're taking corners in excess of 60 or 70 mph, since the wing likely wont be effective below those speeds. On the freeway you don't need downforce, and the added drag will just slow you down.

So, long story short, I think its a really cool idea. But like the other mopar wings and spoilers (go-wing,t/a, ductail etc) I don't think its going to be much of an aerodynamic improvement. It's different, and I think it'll look good, and will probably do about as much as any of the stock wing options (not much). But everyone puts the stock wings and spoilers on, so why not? Looking forward to seeing it finished.
 
I understand about the wings having to be in the airstream. But from what I've read the main reason the wings were as tall as they were on the Daytona and the Superbird was because they had to be sold to the public & if they were much lower the trunk lid wouldn't open. I think the wind tunnel testing had shown they were effective at a shorter height but they were raised for trunk access. I do agree with the part about the vertical stabilizer effect.
 
the trunk lid thing is actully a myth
"Two stories explain the rear spoiler. The common idea is that it's three feet tall so the trunk can open. However, it could have simply been mounted on the trunk in the production cars. An interview with the engineers at Chrysler, long ago, included a comment to the effect that as the numbers kept getting better as they raised the spoiler, until it was three feet off the car, that's where they left it."



I understand about the wings having to be in the airstream. But from what I've read the main reason the wings were as tall as they were on the Daytona and the Superbird was because they had to be sold to the public & if they were much lower the trunk lid wouldn't open. I think the wind tunnel testing had shown they were effective at a shorter height but they were raised for trunk access. I do agree with the part about the vertical stabilizer effect.
 
Thanks guys for the kudos,
When I came up with this, it was one of those lets see if it can be done moments.
As to the functionality of the wing. All wings in all liquids create drag. How you minimize that and create lift is the question. Down force is just lift towards the ground.
In this case, the angle of attack if we were in water, would drag you to the bottom. However in air ( which is just a very thin liquid) the amount of drag and the amount of down force would probably be equal if not offset towards the side of drag. only wind tunnel tests could tell.
Oh, the first pic is of the hydrofoils I designed and sailed in the 80s. My study of aero/hydro dynamics was over a couple of decades, and put me at the forefront of foil sailing in the sailing community at that time. So this was to say I have a little experience here.
the rest of the pics show the boxing in of the underside of the wing. After it was done i put the wing on 2x4 supports on the bench and put most of my weight on it with very little deflection.You would be supprised how strong the original sheet metal shape was without any reinforcement.
As far as taking corners at 60, Id really like to take corners at 90! Keep in mind what the car is being built for.
Andrew
 

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Blue missel what is the PN for the the motor, and do you know where I could get just the motor, for a friend.

By the way, don't defend yourself when these guys have negative comments, just ignore them. You could be a rocket scientist and someone would still question your ability here.

Good work dude!
 
the trunk lid thing is actully a myth
"Two stories explain the rear spoiler. The common idea is that it's three feet tall so the trunk can open. However, it could have simply been mounted on the trunk in the production cars. An interview with the engineers at Chrysler, long ago, included a comment to the effect that as the numbers kept getting better as they raised the spoiler, until it was three feet off the car, that's where they left it."

I'll buy it that they used the trunk lid story as an excuse. But I'm not so sure that they could have mounted it to the trunk lid. The uprights had braces that went through the trunk & down to the floor of the car. They weren't just bolted to the top of the fenders. At least not on the race cars, not 100% positive about the street cars but I think they had the braces too. If the race cars didn't have the braces they probably would have had some strange wrinkles in the quarter panels at 200 mph. :-D If the wings were bolted the the trunk lids they probably would've ripped the whole lid off of the car. They had to do it pretty much the same for both production & race versions because the whole reason for the production car was to homologate the car for racing. :toothy10:
 
here are a couple of pics of the wing on the car for a test fit
of the weatherstripping seal
Andrew
 

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Dude that's sweet. Do u have any more pics of the whole car to see how it flows with the body? Nice work!
 
Its back off of the car for the rest of the metal work.
Keeping the trunk watertight now is the task.
Here are pics of the bottom, the new lip and weather stripping, and of the start of the top skin.
Andrew
 

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here are some pics of the mechanism installed on the new top skin.
Andrew
 

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Here is the video for those not following on the main thread
[ame="http://www.youtube.com/watch?v=Lvmm998V40I"]YouTube - Retractable spoiler for the "Blue Missile" ™[/ame]
Andrew
 
very interesting, I think I would be worried about the very outside edges of the spoiler with out more reinforcing. Sheet metal isn't all that strong and it might bend at the 90mph+ that you plan on having it deployed at.

I do like what you have done with it though, looks good.
-Ross-
 
Ross,
Thanks.
If you go to post #34 you will see that there is some reinforcing where it straightens out, but I wanted to ease the side edge down a bit and because of the compound curve it wont bend. On top of that when I crank the vacuum system up to do a friends Magnum grill I am bagging down a layer of carbon on the underside of the wing.
Thanks again for the thumbs up.
Andrew
 
That is some of the GREATEST custom fabrication I have seen in a LONG time...........Ingenious, clean and Smooooooooooooth.
 
I like the idea, but I would change it a little bit, instead of cutting from the very back of the deck lid, I would have measured one inch in all from the back, that way the spoiler is more square and the deck lid still has the complete shape of the car when the spoiler is up.
But I am def. a fan of this and would buy it. It makes the car very unique.
 
I think I understand what you are saying, and the reason it was cut where it was, was to completely seal everywhere but the long seam. Keeping water out of the trunk is still a concern. But thanks for the kudos.
Andrew
 
I do understand and see why you did the way you did, water would leak down where the legs and mech. are into the trunk. Not meaning to degrade or anything, Cuz really I would/want to buy it! ;D
 
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