Wing Downforce Specs?
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From: Orange County, CA
Originally posted by Earl Needham
Speaking of which -- it seems to me that you could get a lot more efficiency from the wing at a lot lower speed, if the wing incorporated a leading edge slat and a trailing edge flap, just like a regular aircraft wing. I guess it would add some cost and perhaps that's why it isn't done.
Speaking of which -- it seems to me that you could get a lot more efficiency from the wing at a lot lower speed, if the wing incorporated a leading edge slat and a trailing edge flap, just like a regular aircraft wing. I guess it would add some cost and perhaps that's why it isn't done.
FYI, I'm going to take my stock Evo to Willow in Fed or March. Willow's such a fast track, DF goes a long way there - the trick is getting as much DF as possible w/o increasing drag to the point were the net is a slower lap time.
Thanks,
Sean
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From: Orange County, CA
The Evo Press briefing doc states the Evo VIII has a .01 better coefficiency or drag than the Evo VII, but doesn't include Evo VIII's COD. Anyone know what the COD on the Evo VII is, or better yet, an Evo VIII?
...Since MMC didn't include the COD for the Evo VIII in the Evo press information doc, my hunch is that its pretty poor... Maybe .034 or greater.... The technical doc includes just about every other salient technical data point but leaves that out. Weird.
Sean
...Since MMC didn't include the COD for the Evo VIII in the Evo press information doc, my hunch is that its pretty poor... Maybe .034 or greater.... The technical doc includes just about every other salient technical data point but leaves that out. Weird.
Sean
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From: Clovis, New Mexico USA
Originally posted by Sean Hall
Great idea... indy car teams use a flap on the trailing edge all the time to dial in DF w/o changing angle of attack. How much DF would a particular size correlate to on an Evo? How much drag will it it add? TIA
FYI, I'm going to take my stock Evo to Willow in Fed or March. Willow's such a fast track, DF goes a long way there - the trick is getting as much DF as possible w/o increasing drag to the point were the net is a slower lap time.
Thanks,
Sean
Great idea... indy car teams use a flap on the trailing edge all the time to dial in DF w/o changing angle of attack. How much DF would a particular size correlate to on an Evo? How much drag will it it add? TIA
FYI, I'm going to take my stock Evo to Willow in Fed or March. Willow's such a fast track, DF goes a long way there - the trick is getting as much DF as possible w/o increasing drag to the point were the net is a slower lap time.
Thanks,
Sean
Earl
Originally posted by djsbadger
While downforce has no mass, it is a force and weight is a force as well. The beauty of downforce is that it pushes down on the car (like a weight) but it does not have to be accelerated and stopped. For purposes of calculations, downforce which is due to pressure acting over an area, can always be converted to a resultant force acting at a specific location. Because the wing is mounted behind the rear tire, it can reduce the load on the front tires in the same way that a see saw works.
While downforce has no mass, it is a force and weight is a force as well. The beauty of downforce is that it pushes down on the car (like a weight) but it does not have to be accelerated and stopped. For purposes of calculations, downforce which is due to pressure acting over an area, can always be converted to a resultant force acting at a specific location. Because the wing is mounted behind the rear tire, it can reduce the load on the front tires in the same way that a see saw works.
Originally posted by SOF
Try putting a 437 lb weight on the wing, it will break lol.
Try putting a 437 lb weight on the wing, it will break lol.
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Wow, 6 1/2 years since this thread wound down!
Anyway -- the wing makes little to no downforce at any legal highway speed. Most wings only come into play above 100 MPH, and Indy car racers use 140 MPH as the spot where their wings start working.
Anyway -- the wing makes little to no downforce at any legal highway speed. Most wings only come into play above 100 MPH, and Indy car racers use 140 MPH as the spot where their wings start working.
thanks. yes it is an old thread, but a good one
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From: Philadelphia PA
Definitely an important thread. And 6 years later we still have no hard data. I've been wondering about this for years (i.e. the actual specs for the rear wing.) "Chris in HB" had some helpful points... thanks Chris.
Anyway, anyone have any solid info on this? I'll offer my wing for wind tunnel testing.
Anyway, anyone have any solid info on this? I'll offer my wing for wind tunnel testing.
This is interesting about the vortex generator
http://www.mitsubishi-motors.com/cor...004/16E_03.pdf
http://www.mitsubishi-motors.com/cor...004/16E_03.pdf
Evolving Member
Joined: Feb 2004
Posts: 179
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From: Philadelphia PA
This is interesting about the vortex generator
http://www.mitsubishi-motors.com/cor...004/16E_03.pdf
http://www.mitsubishi-motors.com/cor...004/16E_03.pdf
^^ In keeping this zombie thread off topic, and on vortex generators i'll add the following:
"According to the Ralliart EVO MR brochure, the Mitsubishi vortex generator was wind tunnel tested at 180km/h. Vortex Generator Test results (on 180km/h): Rear downforce: + 2kg = 35% UP Air Resistance (CD) : 1.1% OFF" -Quote from a fellow EvoM member.
What we can intone from this:
They are saying "Rear downforce: +2kg UP" and then "Air resistance (CD): 1.1% OFF".
What they are saying is that the rear downforce at the increased speed is increased (UP) by 2 kg (or 4.4 lbs). Since this is a 35% increase this would mean the original downforce was: 12.6 lbs (@180 km/h) and the downforce with the vortex generator is 17 lbs.
Air resistance, Coefficient of Drag (CD), they are talking about the drag coefficient. The drag coefficient is a number that describes the drag a car can have. I say can have because the drag a car DOES have is dependent on it's velocity, frontal cross sectional area, the air temperature and air density that the car is moving through. The drag coefficient is a good number to compare the potential drag a car can have from one to another. From most reasonable sources online that I can see, the Cd for the EVO IX is 0.34 to 0.36.
I won't show the math, but since the Cd is linear in relation to the drag of the car, the car's overall drag at a given speed will be reduced by 1.1%.
Basically all things considered, the reduction in drag is negligible and at high speeds its like adding 4.4 lbs of downforce. Might seem like small gains but it's actually a nice little gain considering you aren't actually adding much to the car. I guess the real question becomes:
The extra downforce in the rear end will either decrease oversteer or increase understeer depending of what condition you currently have... is that what you are looking to do?
If you feel the car is oversteering, then I'd say go for it, if you think the car is understeering I'd recommend NOT doing it.
"According to the Ralliart EVO MR brochure, the Mitsubishi vortex generator was wind tunnel tested at 180km/h. Vortex Generator Test results (on 180km/h): Rear downforce: + 2kg = 35% UP Air Resistance (CD) : 1.1% OFF" -Quote from a fellow EvoM member.
What we can intone from this:
They are saying "Rear downforce: +2kg UP" and then "Air resistance (CD): 1.1% OFF".
What they are saying is that the rear downforce at the increased speed is increased (UP) by 2 kg (or 4.4 lbs). Since this is a 35% increase this would mean the original downforce was: 12.6 lbs (@180 km/h) and the downforce with the vortex generator is 17 lbs.
Air resistance, Coefficient of Drag (CD), they are talking about the drag coefficient. The drag coefficient is a number that describes the drag a car can have. I say can have because the drag a car DOES have is dependent on it's velocity, frontal cross sectional area, the air temperature and air density that the car is moving through. The drag coefficient is a good number to compare the potential drag a car can have from one to another. From most reasonable sources online that I can see, the Cd for the EVO IX is 0.34 to 0.36.
I won't show the math, but since the Cd is linear in relation to the drag of the car, the car's overall drag at a given speed will be reduced by 1.1%.
Basically all things considered, the reduction in drag is negligible and at high speeds its like adding 4.4 lbs of downforce. Might seem like small gains but it's actually a nice little gain considering you aren't actually adding much to the car. I guess the real question becomes:
The extra downforce in the rear end will either decrease oversteer or increase understeer depending of what condition you currently have... is that what you are looking to do?
If you feel the car is oversteering, then I'd say go for it, if you think the car is understeering I'd recommend NOT doing it.