- 2006 WRX STI Rally Car - Something very interesting in the SPOILER
 

https://farm1.static.flickr.com/98/38...73a3d9.jpg?v=0

https://l.yimg.com/g/images/spaceball.gif

Anyone?

Slits in the spoiler? Straighten out the airflow... or what??

What if I added these to my (smaller) spoiler? Any mpg gains by better aerodynamics or what do you think?

probably more for lateral stability at speed. like the rudder in an airplane. I highly doubt it'll help mpgs

agreed.

I have heard that it was used to direct air straight over the wing inline with the body of the car. Because the rally cars spend most of the time cornering sideways they designed this to get air over the wing as it was designed to create more downforce. The angle of that picture gives a nice example of what I am talking about. Normally the air would flow straight up the screen (imagine the car is sliding sideways towards the reader) and go over the rear wing at an angle. The rudders are there to try and redirect the air so it goes straight over the wing parralel to the car.
I don't think this will make any FE difference, unless you take corners so fast that you loose rear end grip and you are forced to slow down.

Cadillac was just so ahead of their time on that one. ;)

Well, I am pretty stubborn so I am going to argue... :D

Like going sideways for rally cars, where air is not directly straight, wouldnt it be the same case during crosswind situations?

And we all encounter crosswinds. So by putting the vanes in there it will direct air behind the car where it was meant to go and not to the side... ?? So it will keep the airflow behind the car straight back instead of sideways...

How about it gives four more points through which the force can be applied?
If it were only mounted at two stanchions the force would require the inverted wing be stiffer (heavier) to prevent collapsing. 200 lbs of force pressing down on the wing when it's supported at the ends will deflect the center. The force would deflect the ends if supported in the center. More support makes it less likely that the Bernoulli effect will break the wing.
The air flow that close to the trunk lid isn't 'clean' enough to warrant any 'rudder' effect. That's the whole reason the wing is raised, anyway.

I don't have to be correct. I just have to raise doubts that you are.

So why the nubbies on top? Haven't a clue.

How about this... Introduce a new design so everyone that already has an ugly 3 foot tall wing on the back of a honda or hyundai has to throw it away, and buy a new ugly 3 ft tall wing with fins on it?

-Jay

its probably a combination of structural support and directing the airflow. the air will have to pass over the car before reaching the spoiler so it'll already be quite turbilent and for the wing to work the air needs to pass over it in the right direction.

u think if there's anything interesing about this car it's the mirrors. and perhaps if you flipped it over there'd be an interesting skid plate wich might have aero proppertys too

The deflector on the back of the roof bears more interest I think for FE aerodynamics. Anything that is designed to make a lot of downforce, typically makes a lot of drag. But feel free to stick one on your front wheel drive econobox if it makes you happy.