Under $20 VG
Evolved Member
Joined: Apr 2008
Posts: 1,016
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From: Denver, CO
How so? The idea behind a VG is to make a vortex that then hits the spoiler. The way the vortex hits the spoiler, it generates even more drag to create more downforce. Even in airplanes, the idea is to create greater drag against control surfaces to create better reactions on those control surfaces. Thus a lower stall speed...
according to mitsubishi, adding a VG to the X should do more harm than good because the X wasn't designed to make use of it. The VG on the IX was engineered to work with the IX wing. mitsubishi said in that tech article they released about the X's aerodynamics that the rear diffuser and underpanels generated the aero they wanted in conjunction with the wing, and it made the VG unnecessary. so that means the wing was never designed to work with a VG. you add a VG made my some company just to look cool, and you're probably screwing up the airflow more than helping it.
also, more downforce doesn't have to equal more drag if it's done right. F1 cars are a perfect example. it is entirely possible, and it's done every day, to increase downforce without increasing drag.
also, more downforce doesn't have to equal more drag if it's done right. F1 cars are a perfect example. it is entirely possible, and it's done every day, to increase downforce without increasing drag.
Evolved Member
Joined: Apr 2008
Posts: 1,016
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From: Denver, CO
Take a look at the formula for calculating downforce from a wing. The drag coefficient is always part of the equation. http://en.wikipedia.org/wiki/Downforce. Increase in drag, can directly translate into more downforce. Remember, if drag is 0, that means when you multiply it by another number, the answer is zero. Therefore, it's impossible to create downforce, without drag of some sort.
Last edited by Webman; Mar 5, 2010 at 09:49 AM.
How so? The idea behind a VG is to make a vortex that then hits the spoiler. The way the vortex hits the spoiler, it generates even more drag to create more downforce. Even in airplanes, the idea is to create greater drag against control surfaces to create better reactions on those control surfaces. Thus a lower stall speed...
More white-paper goodness: Mitsubishi Motors Technical Review
A VG will create more drag on surface that has connected laminar flow. e.g. a flat surface. However, if you curve that surface to the extend that the airflow will disconnect from the surface, then energizing the airflow (making it turbulent) will allow it to stay connected to the surface at much larger angles of attack. This is why in some cases a VG can lower drag. In the case of the airplane control surface or wing, it is allowing the flow over the control surface and higher angles of attack. Likewise, an airplanes "stalls" when the flow over the wing disconnects, and therefore a vortex generator will increase the stall angle of the wing.
This is why golf ***** go farther with those little pock marks, because those pock marks energize the air around the ball and allow it to flow in a connection fashion across more of the ball. Hence, less overall drag.
In the case of your X, the real question has to do with the flow of air over the back window. If that flow is disconnecting from the window surface, then you will reduce drag by energizing the flow before it disconnects, and allowing the air to "follow" the contour of the window. If it is not disconnecting, then a VG will increase drag because it was not necessary in the first place.
VGs solve a very specific airflow problem, and if you don't have that problem they are not just useless but actually do increase drag on your car. If mitsubishi says you don't need them, it's probably because they've tested it and found that you don't need them. Look at the angle of the rear window compared to the roof on a IX, and you can see immediately why a VG would help that car.
This is why golf ***** go farther with those little pock marks, because those pock marks energize the air around the ball and allow it to flow in a connection fashion across more of the ball. Hence, less overall drag.
In the case of your X, the real question has to do with the flow of air over the back window. If that flow is disconnecting from the window surface, then you will reduce drag by energizing the flow before it disconnects, and allowing the air to "follow" the contour of the window. If it is not disconnecting, then a VG will increase drag because it was not necessary in the first place.
VGs solve a very specific airflow problem, and if you don't have that problem they are not just useless but actually do increase drag on your car. If mitsubishi says you don't need them, it's probably because they've tested it and found that you don't need them. Look at the angle of the rear window compared to the roof on a IX, and you can see immediately why a VG would help that car.
Even with my limited knowledge on aeronautical engineering, I know that any type of item you put on top of a flat surface with uninterrupted airflow, creates drag. Think back to the days of Howard Hughes. The only way he was able to beat so many speed records was because of his innovations in aeronautical design. Making rivets flush on the body was what gave him the most speed.
A VG on an airplane, is used on wings to create a vortex that can essentially improve the effectiveness of control surfaces after the VG. If anything, the only thing you are gaining is greater effectiveness of your spoiler, which is offset by increased drag because of the VG. On a plane, a VG can give an aircraft a greater max takeoff weight, as well as reduce the stall speed. But, again, it still brings about more drag. So while you can create more stability with a VG, you are always creating more drag, no matter how well designed the VG is.
Because a VG creates drag, there's no way you are getting better gas mileage.
Bseides, how in the hell do you even pull off 17mpg anyway? My foot is so heavy that I'm lucky if I get 14 out of my daily drive, which consists of 5 miles of highway. The average is 11-13mpg for me. But when I hit the highway and set the cruise control, I can easily hit 23-25.
A VG on an airplane, is used on wings to create a vortex that can essentially improve the effectiveness of control surfaces after the VG. If anything, the only thing you are gaining is greater effectiveness of your spoiler, which is offset by increased drag because of the VG. On a plane, a VG can give an aircraft a greater max takeoff weight, as well as reduce the stall speed. But, again, it still brings about more drag. So while you can create more stability with a VG, you are always creating more drag, no matter how well designed the VG is.
Because a VG creates drag, there's no way you are getting better gas mileage.
Bseides, how in the hell do you even pull off 17mpg anyway? My foot is so heavy that I'm lucky if I get 14 out of my daily drive, which consists of 5 miles of highway. The average is 11-13mpg for me. But when I hit the highway and set the cruise control, I can easily hit 23-25.
VGs solve a very specific airflow problem, and if you don't have that problem they are not just useless but actually do increase drag on your car. If mitsubishi says you don't need them, it's probably because they've tested it and found that you don't need them. Look at the angle of the rear window compared to the roof on a IX, and you can see immediately why a VG would help that car.
Evolving Member
Joined: May 2009
Posts: 153
Likes: 0
From: Davie, Florida
this is the reason why they need to limit selling evo's to people who respect a nice and fast car.
these clips are the absolute reason why evo's have a rice rep....
in other words, Take them off
these clips are the absolute reason why evo's have a rice rep....
in other words, Take them off
I figured that since its an ebay one and that my car is slow it wouldnt really matter