Does any one have any figures as to how much Down Force the stock wing creates at a specific speed. People are constantly saying they feel this huge difference when they take their wing off but I just don’t believe it to be honest.

 

Check out the 2003 Review for some good data on the wing

http://www.mitsubishi-motors.com/cor...w/e/index.html

 

Thanks for the link but the only thing I see in that paper is this excerpt

Further, the
rear spoiler is, thanks to the adoption
of carbon-fiber-reinforced plastic,
stiffer and thinner with a more
effective wing section that generates
more downforce without
increasing drag. (Page 115)

Is there something that I am missing?

 

sorry, try page 13 of the 04 review, it had been a while since i had looked @ this

its actually more about the Vortex generators than the wing, but there is still some good info

 

That is slightly more useful. I would still really like to find data on just the spoiler. But I think the fact that the reduction in drag coefficient and the reduction in lift coefficient of only .006 @ 110 MPH is not very significant.

 

Definitely interested in this. Subscribed.

 

It was reported in one of the car mags a couple years back... I believe it was 58lbs of downforce at 110mph. The MR's vortex generators supposedly increased that to ~62lbs. These numbers are from memory. I may be off a bit, but they should be quite close. This is the only time I've ever seen real numbers quoted.

Sport Compact Car made a reference a couple issues ago that they'd have a detailed wing study coming up in a future issue, but I haven't seen anything yet.

 

I can't remember exactly which car magazine I read this in, but it was either Car & Driver, Road & Track, or Automobile (because those are the ones I get) that compared the MR to the RS.

I don't recall the year, but I believe it was '04, and I think the track was Streets of Willow (meaning it was likely R&T). They did not measure the downforce, but they did say that the MR felt more stable under braking from 80 MPH plus at one of the turn entries. Nothing dramatic, but noticeable; the RS reportedly wiggled a bit, whereas the MR was solid.

They did not think that it was the lack of ABS as they were not near lockup. They did speculate that, although the amount of downforce was most likely modest, the RS might actually have lift at that speed, making the difference all the more noticeable.


FWIW.

 

I believe Motor Trend made a similar comment (I know I read it in two different magazines, but I don't recall which ones).

 

Anyone got downforce figures on an 06 STI?

it felt like it had more downforce than my 06 evo when i had the STI, but then the evo has been at stock ride height until I pick it up 2morrow and also doesnt have the vortex generator or any wing lip or front lip or splitter installed. so i suppose I need to do those things first.

splitter ripping off thats just silly argh gotta get one that bolts primarily to chassis or what-not


Trav

 

One of those same articles did mention the STI wing's downforce. I remember it was definitely less than the EVO's.

None of this means anything though if you don't know how much inherent lift each body has to start with (overall vehicle body, not just the wings).

Personally, I always felt my WRX (not STI) was much 'lighter' and unstable at high speeds than my EVO, but there's really no way you can consider the subjective feeling to be relevant to measured lift.

 

I don't know what the heck all this means, but it's supposed to actually measure downforce...

http://www.arcinter.co.jp/arc/produc...t/dfm/dfm.html

 

I cant imagine that 58lbs at 115 MPH creates a noticable difference. And that is at 115MPH, at more modest speeds like 80MPH i think it would be almost impossible to notice a difference.

 

https://www.evolutionm.net/forums/sh...highlight=drag

 

I think it depends on the downforce generated compared to the total weight of the car.

If you look at it in the most simple way, the centrifugal force = m x v^2 /r ; and this balances with mu x R (at the limit of adhesion).

Obviously we want maximum v. By adding downforce, we're changing R and effectively if we're talking about the same corner we're want to increase R/m.

Without neither downforce nor lift, we've got v^2/r = mu x g.
With 'D' newtons of downforce, we have v^2/r = mu x (m x g + F)/m

So, v(before)/v(after) = square root (mg+F)/mg

Let's say the evo is 3500lbs = 1590kg and we're making 58lbs = 259N of downforce then v(before)/v(after) = 1.0083
If you went around at 100mph without downforce then you can do 100.83mph with downforce.

If we have a light car of 2200lbs making the same downforce the v(before)/v(after) = 1.0131, so the same wing can be said to be more effective. Obviously this will come to play only when you're right at the limit of things.

Obviously this is a hugely simplistic view of things but I hope it gives an indication of what's going on. I think mostly with road cars the downforce goes into combating lift rather than actually making the car press against the road more.

Another effect of aero devices I suspect is to help stabilize the car, rather than going for all-out downforce. Additions of zero-lift kits and various other bits really do make the car feel more stable.