wing design/theory

[The Stickman]

Actually GM found out that air tends to come out from under the truck, swirls up pver the bed and hit the back of the car. Take a look at there GMC LSR truck and any info you can find on it. They figured out that a 2/3rds length tonneu with the front of the bed open was the best. When I raced my S-10 I made a very cheap and light one with thin aluminum angle for the sides and a few cross supports and then skinned it with very thin sheet aluminum and used pop rivets to hold it together. Worked well enough. Never needed any downforce.

[chicane67]

High "turbulence" no... high "pressure" yes.

If the smooth flow of air is interrupted over a wing section, "turbulence" is created which results in a loss of lift, or in your case downforce... and induces a high degree of drag. An airfoil designed for minimum drag and uninterrupted flow of the boundary layer is.

The idea of a "wing" is to add downforce without inducing drag.

This is a basic program that will lend you some insight:
http://learn.arc.nasa.gov/products/p...s/foilsim.html

And then... this is a little more indepth. You just need to think of this upside down:
http://www.lerc.nasa.gov/WWW/K-12/ae...let/vj402.html

[HectorM52]

This might be a good photo to show that our trucks ARE getting some good downforce in the mid-bed area.

So let's get this wing / spoiler worked out!

[The Stickman]

This might be a good photo to show that our trucks ARE getting some good downforce in the mid-bed area.

So let's get this wing / spoiler worked out!

Or it could be like I said where GM found out the air swirled up and into the bed from under the truck?

[HectorM52]

Or it could be like I said where GM found out the air swirled up and into the bed from under the truck?

Yeah...

Never before have I wished for smoke, but it would have been cool to see it curling up from under there like the wind tunnel tests! :D

[The Stickman]

Yeah...

Never before have I wished for smoke, but it would have been cool to see it curling up from under there like the wind tunnel tests! :D

I know some guys that did it using string on a Fiero and they found that the air would come backwards under the wing then into the into the swirl coming off the roof. Now all I know is what I read so I might not have all the story. But I do know I didn't need a wing when I ran on road courses. And I was running the long starights at Pocono to over 110mph. How much over I don't know as I was going by what the guy in the M3 I was following told me. My speedo went to only 85mph. But I also ran at Watkins Glen with it and again had no problems with rear grip.

[AJSZR2326]

downforce will start to apply at approx 75mph and above but unless the whole bottom of your truck or car is sealed off , a wing(spoiler) isnt going to do anything. my experience comes from a 02 lingenfelter z06, then applied greenwood complete kit front to back. and yes nobody liked the huge wing in the back but it is functional.

[trackrat79]

This is my home made bed cover. noticeably more stable at speed.


eventually i want to do a full chassis with a complete under body or belly pan. and i want to blend the bed into the back of the cab and get ride of the gap between the bed and cab to create a more smooth flowing body.

[Norm Peterson]

You'll need to add a lot of structural rigidity in the region where the cab ends and the bed begins (with something at least as high up as bed top height meeting cab region structure at the same height). Stock, that gap can close up a LOT as you drive. Anybody old enough to remember being able to ride in the bed without getting hassled for doing so knew enough to keep their fingers out of that gap, either from being told just once or from painful experience. That much movement will tend to buckle any sheetmetal that's trying to resist it unless it is very carefully designed/sturdily fabricated.


Norm

[trackrat79]

O I know. i was one of those kids that got his fingers pinched. (Once, and i repeat once.) I stayed towards the back from then on. Not that chancing having the tailgate open up and falling out the back was better but hey.

Anyway, the truck is getting a full tube chassis, cage with full length down bars from the main hoop of the driver cage down threw the upper cab into the bed to were the chassis goes up and over the axle. So im not to worried about flex. At one point i was thinking about trying to find a blazer body and graft the back wall and roof of a pickup cab to it.