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haven't read anything on car aerodynamics in detail, but im assuming the shape in the picture I posted, similar to a aircraft aerofoil would be most efficient, and i saw a couple guys once with maybe 20-30 degrees angle of attack on the rear wing of their car, in hindsight wouldn't this create a shit load of drag and not create any 'lift' downwards???

post-20826-1237379512_thumb.jpg

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Matt, let me first say that CFD software was not cheap or acessible when i was doing it around 2000-2001. Dont know these days. But what i can almost guarantee is that irrespective of cost and access these days you need to have a thorough understanding of fluids mechanics if you are to have any hope in hell of being able to do any meaningful CFD.

Reading a book on race aero will give you more understanding then trying to use CFD as a tool. CFD software means the user has to make many base assumptions, which can mean shit in shit out. There are plenty of small level open wheelers manufacturers who with their teams of engineers do CFD only to find that in testing their CFD model was floored by said assumptions. Hell you read the same thing about F1 teams every year having the same problem.

So it can be cool and novel to play with if you have access....but i genuinely believe you need to have an engineering degree with a good comprehension of fluid mechanics combined with several years of industry experience in fluid mechanics if you are to have any hope in hell

LOL, easier to read books and use good practice then substantiate with seat of pants or any data acquisition you may have

Maclaren ATM being the latest aero package victim.

haven't read anything on car aerodynamics in detail, but im assuming the shape in the picture I posted, similar to a aircraft aerofoil would be most efficient, and i saw a couple guys once with maybe 20-30 degrees angle of attack on the rear wing of their car, in hindsight wouldn't this create a shit load of drag and not create any 'lift' downwards???

post-20826-1237379512_thumb.jpg

My understnding is that, with a single element wing, anything more than ~12 degrees will start to produce flow separation, which is not a good thing. Multi element wing's performance are a different thing altogether and are certainly beyond most amateur's expertise.

My understnding is that, with a single element wing, anything more than ~12 degrees will start to produce flow separation, which is not a good thing. Multi element wing's performance are a different thing altogether and are certainly beyond most amateur's expertise.

a multi wing aircraft just allows more lift to be produced in the same wingspan over a less efficient aerofoil

multi element aerofoils should be able to produce more downforce for the same wing span.

fatter aerofoils produce more lift at lower speeds but more drag at higher speeds, skinnier aerofoils produce more lift at higher velocities though,

now im thinking the shit planes we fly use very fat wings and we cruise around 160kph, wouldnt a car aerofoil which probably see's most its use around 100-200kph need a fatter aerofoil too? most the D1 style wings are just a slightly curved flat piece of carbon of firbeglass

  • 1 year later...

Hi guys,

Just dredging up an old thread, as it's got quite alot of useful info in it already.

In the rules for the race category I'm trying to compete in there are two options for rear wings:

1. Rear Wing (factory std); rear wing assemblies fitted as factory standard by the vehicle manufacturer are permitted but must remain unmodified.

2. Rear Wing (non-std) for all other vehicles; it is permitted to fit a non-standard rear wing assembly provided that it is single element and complies to the dimensions in Diagram 3 (shown below). They also must not extend further rearward than the extremity of the rear bumper.

post-1397-1287103001_thumb.jpg

I currently have a non-std GT Style Wing, which well exceeds the dimensions shown in Diagram 3, however I could modify the stays to make it fit within the dimensions.

post-1397-1287103397_thumb.jpg

Or

I could purchase an R33 GTR wing, which was apparently an option on GTS-t's, and utilise the standard wing adjustment

post-1397-1287103262_thumb.jpg post-1397-1287103275_thumb.jpg

Thoughts on which might be the better option ?

I've found the std R33 GT-R rear wing to be pretty good, and it can generate some pretty good downforce. But i've never compated it to a gt wing

you going to run in IP?

Edited by sav man
I've found the std R33 GT-R rear wing to be pretty good, and it can generate some pretty good downforce. But i've never compated it to a gt wing

you going to run in IP?

Did you actually change the angle of the wing element ?

Street Cars (a WA Variant of Sports Sedan - CAMS 3D)

http://www.wascc.com.au/Docs/2010/V1-9_Str..._2010-04-01.pdf

GTR wing (and entire kit) was a factory "option" on GTS-t's. Hence we are allowed to run GTR wings, Nismo lips, front bar etc for them in rallying under CAMS and AASA.

I believe the 33 to be the same deal.

Personally, given those miniscule dimensions of the aftermarket wing allowance, I'd run the 33GTR version. IMO, all you'll get with that aftermarket wing is drag and bugger all downforce. I'm not expert though.

Did you actually change the angle of the wing element ?

Street Cars (a WA Variant of Sports Sedan - CAMS 3D)

http://www.wascc.com.au/Docs/2010/V1-9_Str..._2010-04-01.pdf

Yep. I was surprised when I could feel the difference, the car used to have to run hicas. Which made it very nervus under heavy breaking. Wound some more wing blade on, and it made the car heaps better to drive.

Yep. I was surprised when I could feel the difference, the car used to have to run hicas. Which made it very nervus under heavy breaking. Wound some more wing blade on, and it made the car heaps better to drive.

What Ben Said. I replaced the standard blade with a carbon one and inadvertantly set it at a much more aggressive angle with the same result. The car was more stable everywhere Noticeably under heavy breaking and at straight line high speed.

GTR wing (and entire kit) was a factory "option" on GTS-t's. Hence we are allowed to run GTR wings, Nismo lips, front bar etc for them in rallying under CAMS and AASA.

I believe the 33 to be the same deal.

Personally, given those miniscule dimensions of the aftermarket wing allowance, I'd run the 33GTR version. IMO, all you'll get with that aftermarket wing is drag and bugger all downforce. I'm not expert though.

Thanks for the confirmation, I doubt anyone would try and complain about using a factory optioned wing :thumsbup:

The GT Wing definately generates some downforce, as you can feel the difference when it's not on, but I do agree the drag could be considerable, but easily overcome with 500rwhp :)

Yep. I was surprised when I could feel the difference, the car used to have to run hicas. Which made it very nervus under heavy breaking. Wound some more wing blade on, and it made the car heaps better to drive.

Good to know, think I'll give it a go :)

Anyone used the Voltex wings before? http://www.voltex.ne.jp/english/pro_wing.html

Lots of the top level Jap guys use them. Thinking of getting the "type 5" one for my build later on :whistling:

Anyone used the Voltex wings before? http://www.voltex.ne.jp/english/pro_wing.html

Lots of the top level Jap guys use them. Thinking of getting the "type 5" one for my build later on :P

I bought one earlier this year, amd yet to try it though. Supposedly the ducks guts though, so we'll see.

post-8405-1287370566_thumb.jpg

post-8405-1287370580_thumb.jpg

Single plane, I wonder how much better worse they are then other things out there. There is plenty of info around that suggest dual plane elements are the way to go....and they want 2k for their Type 3/5 style wings :P

Edited by Roy

Personally I think the Voltex styles are fine (and creat real downforce), but, I think it wise to have an excess of horsepower to push them through the air...... to me they just don't look like they'd be very slippery.

We can hypothosise for weeks about this shit though I guess....... we always seem to :P

had a meeting with voltex the other day in japan. they are nice guys so I am a bit biased but they certainly test all their gear as best they can and do target the time attack/circuit market more than the auto-salon/street car market which says something about what their wings should do. there is no doubt their own cars do have functional aero as their corner speed cannot be got just through chassis/tyre grip and big balls. but their own cars have a lot more than just a wing, they have a whole package of bits designed to work together.

how a wing will work on a car that has any number of other parts on it (body wise) is anyone's guess. even ride height can affect aero balance once we are talking about splitters and under-trays etc. let alone how much different front bars or different under body stuff (or lack of) will affect it.

so throwing ANY brand of wing at a car is a bit of a shot in the dark but as far as those guesses go then the voltex one is probably less of a gamble than most.

I am also sure of the benefit of this c-west wing. http://www.c-west.co.jp/gtwing/gtwing2.html it's been proven many times on circuit cars all over the world. but if you want one with some decent down force be sure to buy the optional gurney flap too. it's key to it's usefulness on track.

they also now have the neo which is dual plane. http://www.c-west.co.jp/gtwing/gtwingneo.asp the benefit (as my small brain understands it) should be more downforce without a significant increase in drag.

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