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View Poll Results: What type of tail
Turbo
19
16.81%
Carrera
33
29.20%
Duck
33
29.20%
none
28
24.78%
Voters: 113. You may not vote on this poll

Tails!

Old 08-23-2011, 11:30 PM
  #31  
kusee pee
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For IB cars my fav is the Weissach tail from the SC of the same name, closely followed by the carrera 3.0 tail. The former is hard to come by, hence I've just fitted the latter to my SC. But I agree that tails are very car-specific. For me, anything too far from a period look is against my preferences. Overall I prefer a tail to a clean lid.
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Old 08-24-2011, 11:59 AM
  #32  
SARGEPUG
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Originally Posted by Ed Hughes View Post
Actually, it is reduction of lift, instead of downforce, to be specific.
Isn't that the same thing?? The air the wing catches, keeps it down, hench it wont lift. haha
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Old 08-24-2011, 12:22 PM
  #33  
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i dont think so .. i think if you were to weigh your car standing still and at motion it would get lighter ,, as the car lifts. ( if you could do that of course ) . the wing would cause it to get "less light" by removing lift.

To provide downforce the car at speed would appear heavier than when stationary as the force pushes it down.
I dont think any of the wings on our cars provide down force. This may be way off base but this is how i reasoned it in my tiny mind.

especially if you take the wing off and look at it in a profile shot .. The car as basically an upside down airplane wing. The air going over the top has a lo further to go than the air going underneath there for the pounds of pressure per square inch is less on the top than on the bottom "lifting" the car.
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Old 08-24-2011, 12:37 PM
  #34  
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Ed and Ice are right. There is a difference between downforce and negetive lift.
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Old 08-24-2011, 12:54 PM
  #35  
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Yep, many racecars, for many years, have had aero and ground effects features that do provide downforce, enough that some could run upside down at speed. We can only really hope to help Mother Nature retain her gravitational pull.
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Old 08-24-2011, 12:57 PM
  #36  
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not exactly downforce but awesome
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Old 08-24-2011, 01:03 PM
  #37  
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Thats why they have to weld the manhole covers down on city street tracks(long beach). GTP cars could pull them up at speed.
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Old 08-24-2011, 04:04 PM
  #38  
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Was that a stock color wolf??
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Old 08-25-2011, 01:52 AM
  #39  
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Originally Posted by whalebird View Post
Thats why they have to weld the manhole covers down on city street tracks(long beach). GTP cars could pull them up at speed.
I pulled a manhole cover in a school zone while street racing a guy on my way to work today. I hate it when that happens because it's only right to circle around the block and put it back.

(My targa has a carrera tail with the correct chin spoiler)
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Old 08-25-2011, 01:59 AM
  #40  
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Originally Posted by Mark Harris View Post
I pulled a manhole cover in a school zone while street racing a guy on my way to work today. I hate it when that happens because it's only right to circle around the block and put it back.

(My targa has a carrera tail with the correct chin spoiler)
yes this happens to me all the time. That's why I'm deleting the tail!
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Old 08-25-2011, 11:53 AM
  #41  
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Read this and go up to "Airfoils".

http://en.wikipedia.org/wiki/Downforce#Rear
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Old 08-25-2011, 12:39 PM
  #42  
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Originally Posted by SARGEPUG View Post
Read this and go up to "Airfoils".

http://en.wikipedia.org/wiki/Downforce#Rear
OK, read that, and look at the pics they show. Then go to the R&T or C&D article on the Porsche ducktail, and some other published data that shows Porsche was able to reduce lift on the cars via the tails in the 70's and 80's.

I'm going off memory, but the car in the mag test took 250 or 300lbs of lift (measured via an articulated bicycle wheel affixed to the back of the car) and took it down to 80 or so.

Now, with a GT3RSR, anmd certainly Formula and prototype race cars, there are aero aids that provide true downforce. But the rudimentary achievement of a basic tail, at the speeds our cars run, is that it is a "spoiler" that negates lift. The shape or a 911 and an airfoil are quite similar.
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Old 08-25-2011, 12:54 PM
  #43  
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Originally Posted by Bill Verburg View Post
Dr. White, the author of the Pano article didn't specificlly say what front spoiler was used w/ the duck rear. but I suspect that the subject car was a '74 G series which would have had a p/u SC lip.

anyhooo, here are some #s and the cars that they come from






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Old 08-25-2011, 01:23 PM
  #44  
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....and there it is! Well, I got the amount of lift right, I guess I was optimistic on the spoiler's effect, in my case-the duck. The brain ain't as sharp any more.

But, this shows that lift starts to come on strong at about 75 or 80mph. A tailed car can feel much more sure-footed at highway speeds in this range. As noted earlier, the pop-up tails come up at about 50.
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Old 08-25-2011, 02:12 PM
  #45  
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It looks even more like an airfoil from the back which makes me wonder if I could go Wright Brothers in reverse. Maybe with a Steve Wong chip.

Seriously, I wonder if anybody ever turned it backwards in the wind tunnel to see what kind of lift it generated. It might need one of those NASCAR roof flaps to stay planted.

Edit: never mind. The leading edge looks less like an airfoil from the back.
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