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I posted this in the exterior section to but I just wanted the most possible feedback before I swap out my spoiler for an 04 wrx trunk that has no wing at all. I much prefer the look of no spoiler, so I dont need convincing to keep it, but I am wondering how much the spoiler REALLY affects high speed handling, 1/4 mile, or overall stability. I mean, theorhetically(however you spell that) removing the spoiler and then taking a turn at 100mph+ and your rear wheels and maybe front ones will have less downforce causing a slide that would not have happened and could be VERY dangerous at that speed. But does anybody know if this spoiler really does all that much? Much obliged to anyone with real info on this
 

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i don't think it actually creates any "downforce", but it greatly reduces "lift", and should really have an effect on how the car handles at speed. check out the thread posted above...
 

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It'll only matter at high speed, and then, probably only in cornering situations.

It might even improve your 1/4th mile time, simply because the car will be lighter without the wing... but probably not a noticable difference.
 

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there is some downforce generated by the wing. how much?

well, someone with access to a wind tunnel can finally put this mystery to an end. (or someone with some understanding of fluid dynamics too... ;) )
 

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Understanding it is one thing, being able to quantify it is quite another.

It would take a pretty complex computer model of the wing.... probably laser measured.... to conclude this without wind tunnel time.
 

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norcal-sti said:
i don't think it actually creates any "downforce", but it greatly reduces "lift"
ummm, aint opposite of downforce is lift...

so if you turn the wings of an aircraft upside down, it will reduce the "lift" by the now downfore generated... ;)
 

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LOL!

That's an excellent observation.... I think the statement still applies (the wing channels airflow, so it really is just stopping the lift force from being created, instead of [or maybe in addition to] creating downforce).

But that's a hillarious way of seeing it.
 

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jeez, you guys are ruthless. it is different. downforce is actually pushing the car toward the ground. lift is pulling it away. neutralizing lift is different from creating downforce. most race cars w/ wings use them to balance the car with smaller amounts of downforce than the chassis itself creates. check out F1 racing (magazine) someday. in the back, they have a section called "debrief", and they go over the tweaks made to certain cars at each event. it's amazing the small differences between cars, even on the same team that are made to suit a particular driver. if you don't think our wing does anything, take a look at some of the tiny gurney flaps that teams run on front wings.
 

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OK please no flaming that I'm not an aeronautical engineer, this is just my $0.02. I used to be a helicopter mechanic so I know basic aerodynamic theory. If you look at the shape of the rear wing on the STi and the EVO you notice it is an airfoil. It is the exact principle as an airplane wing, only flipped upside down. An airfoil works, in case you don't know, by creating a difference in pressure between the top and bottom surfaces, by making the air travel a longer distance over one side than the other (The longer side sort of spreads out the air molecules making a low pressure area). Whether or not it is cancelling another opposing force, it is still creating downforce. By doing this, it is also creating drag. Another thing no one has mentioned is straight line lateral stability at speed. If you notice, there are prominant vertical surfaces on both the EVO and STi wings. These are known on aircraft as vertical stabilizers. They basically help keep the car pointing straight, like fins on a rocket. I have no idea as to how much these affect driving, but just stick your hand out the window doing 60mph & play around with it...multiply your hand area by maybe 40? and that's probably the area of either of those gigantic wings, and IMHO it must be a substantial effect.
 

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The Project STI vehicle's trunk and wing has been removed in favor of a 2004 WRX and wing. While there are reasons to believe that the STI wing is functional, the wing attracts a lot of attention. Any difference when driving either on the freeway or on city streets is not substantially noticeable. At speeds above 100 mph, the STI feels incredibly stable with the STI wing; almost as if it were slicing the air like a sharp knife slicing cheese. At that same speed with the WRX trunk and wing installed, however, the car is only slightly less stable, but in no way will the car loose traction and spin out because the wing is off the car. I really enjoy driving the Project STI vehicle around and not having every Tom, Dick, and Harry pointing at me either when I drive by or am stopped at a light. If you plan on tracking the car frequently, it would be to your benefit to retain the stock STI wing.
 

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I was planning on trading my STi trunk and wing for a WRX trunk and wing until Thursday of last week. I was driving home from work and it was fairly gusty. At one point on my drive, a gust of wind hit my car at an angle (driver front to passenger rear). I felt the car's butt suck down to the road. Now if that was not downforce, I don't know what is. I have had many different cars in windy conditions and never felt that before. I am keeping the wing by the way. :D
 

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Project_STI said:
I really enjoy driving the Project STI vehicle around and not having every Tom, Dick, and Harry pointing at me either when I drive by or am stopped at a light.
It's weird. When I first got mine, I had the same feeling about everyone in the country noticing the car, pointing it out, etc. Now, it's like no one really notices or cares anymore. And to be honest, that is more than fine with me. I didn't buy it to show off or be the center of attention.

First few days after buying it, I had 2 or 3 different cops check me out carefully and I was really worried that when I tinted my windows I was going to get hassled. Strangely, though my windows have 22% tint film on them now, almost every cop I've seen since then doesn't even look at me. And I've seen and driven by plenty of them.

I think it's a non-issue now. I know my own personal attitude now is "who cares" since I have gotten the car broken in and experienced some more spirited driving, I know what this car is all about and could care less what someone else thinks of its looks. At least I can tell people that it is the factory stock look! :D

I still get the occasional driver in the Saab or BMW or something that seems to become enraged by my huge wing or hood scoop and needs to prove their manhood, but generally it's in town in traffic and I just let them blow by me and go on their merry way believing they dusted some dude in a pimped out ricer. :D Whatever. I'm not the ego police, they aren't my problem. :lol:
 

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Where to find (dash pocket with a flip cover)???

The trunk spolier is definately functional. My buddy just got back from Watkins Glen a few weeks ago. He told me that when he was at 140 mph it was rock solid until the top of the wing snapped dead center. It isnt a through and through break but it is VERY flexible if you push on the top of it. This is telling me that it is creating an incredible amount of downforce.
 

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archangel said:
He told me that when he was at 140 mph it was rock solid until the top of the wing snapped dead center.
I don't get it. Several people here have gone over 140 mph and not snapped their wings. What was done to that wing prior to make it so weak and ready to snap?
 

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Pirelli P Zero Nero M + H

I've hit 145 twice now and no snapping has occured on mine. And btw 4g63 nice explanation of the basic cocepts on air flow.
 

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2 door STi photochop

I've been a Porsche guy all my driving life (age 52), Early Turbos, circa 1979 with the whale tail sporting the thick rubber trim were producing some 800 - 1000 lbs of weight on the rear of the car at 100mph+. There was an article of the difference in rear tire wear under normal cruising with the wing vs without. I doubt that a wingless STi is dangerous but the wing is definatley functional. How much?? Someone above is correct, we need wind tunnel info. RW
 

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The Tire Rack actually did wind tunnel testing on the WRX with various configurations from no spoilers to ProDrive front and rear. The net results as I recall were that the unspoilered WRX was generating measurable lift at 100 mph, the stock spoiler cut that in about half, and the ProDrive package eliminated lift entirely at both ends of the car - giving it the most balanced forces at high speed (or essentially keeping handling the same regardless of speed). The STi aero seems modeled after the ProDrive package, so it's probably a fair guess that it performs similarly until somebody demonstrates otherwise.
 

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Great post.....hadn't heard of that one before.

The thing to remember (as your post points out so well)....our wing isn't generating downforce....it's reducing lift.
 

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exactly! glad someone finally can back me up on that... :D
 
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