GT42R

Used GTC 200 and 300's will probably run $600 or more though, no? Nascar wing being under 600 doesnt sound too bad.

ZX-Tex

iTrader: (15)

Actually I am looking at a COT wing right now. We'll see what happens.

Interesting side note... When I was researching the COT wings, I found a paper from some Engineers that had done aerodynamic modeling and flow testing of those wings. The premise of the paper was to show whether or not there was significant uplift when the car is traveling backwards (AOA is the wrong way). In other words, when the car spins and slides down the track backwards, does the wing lead to the car becoming airborne? Turns out the wing created significant upward lift, or at least took a lot away from the net rear downforce. Thus it was deemed a hazard. I do not follow NASCAR, but apparently that is the reason why NASCAR got rid of the wing on the COT and went back to trunk spoilers.

It is not a problem for us going say 140 mph and spinning on a long straight, but for a NASCAR traveling backwards at 200+ MPH it is a problem. Aerodynamically, that is a HUGE speed difference. Interesting, I do not think I have ever seen this discussed in an aero oriented race series like F1, ALMS, whatever. I guess they know more than the 'hick moonshine runners' do

ZX-Tex

iTrader: (15)

So I found a COT wing for less than $500 shipped and it is on the way. I will still need to move the mount points on it as well so I'll post up the results of that if anyone is interested.

GT42R

What's this COT wing exactly?

hustler

iTrader: (6)

Google, how does it work?

ZX-Tex

iTrader: (15)

COT = Car of Tomorrow ~ NASCAR effort to modernize vehicle aerodynamics

COT wing is a one-design $3000 carbon composite wing made by Crawford Composites for NASCAR COT cars. Well designed, well constructed, good L/D ratio (better than my dual element aluminum APR wing). Interchangeable end plates made for different tracks (road course, ovals). NASCAR dropped the wing and went back to spoilers for the aforementioned reason of backwards flow uplift.

Ergo, inexpensive bad-*** wings available for relatively very cheap prices on the used market.

hustler

iTrader: (6)

Contact me if you see one on the cheap.

TheBirdmanJD

iTrader: (2)

$400 - Damaged
(Looks like the duct tape fix worked for NASCAR)


If you don't care how the repair looks, that could be a DIY fix. Not sure if that's really enough of a deal over a new GTC-200 though...


Bird

rlogan

iTrader: (21)

I've started a trend...too bad there aren't more available. Remember, there are two different versions of the wing, one for show and one for function. More tech here...

https://www.miataturbo.net/race-prep-75/new-wing-test-62253/

Key points:
1) should have CNC aluminum finish on ends(with end plates off)
2) built in slot for wickerbill.

If it does not have these elements, it is a wing built for show only!

ZX-Tex

iTrader: (15)

Yes kudos to Ryan for coming up with this approach. As much as most of us road racers generally dislike NASCAR, it is ironic that in effect we are being partially subsidized by them with this wing purchase.

monkeywinky

What did you end up doing for this? It seems you have the ability to make custom mounts, why not make new angled uprights that a universal gtc will mount to? Ill try to cad what i mean when i get back to the office, but essentially make uprights that mount to your current license plate width then flare out to the 42.5" span to bolt to the gtc uprights. You would retain the turnbuckle adjustment of the gtc

monkeywinky

I changed my mind about my previous suggestion. The width it would need to span in order to go from 12" to 42.5" without making the wing too high in the air would make the angle pretty small. Instead, you could eliminate the apr mounts altogether and make something like this to bolt up to the available mounts on the wing. I'm not sure what wing you're getting or the details on how it mounts etc...but maybe this will give you a few ideas.

I forgot to "dimension" the angle, but a quick calc yields something around 31.24 degrees.

ZX-Tex

iTrader: (15)

Monkeywinky yes I could do that but without at least some truss cables it is not going to be as structurally stable or as stiff as what I have now. Plus, between the cables and the above brackets, the additional cross-sectional area compared to what I have is going to add drag, not to mention disturb the flow over the wing. What I am doing now is less obtrusive.

BTW you need to go start a post in the meet and greet section.

GT42R

I like how your current mounts are done. I am building my wing mounts now, and I'm trying to tie it directly into the chassis/cage, while meeting some other requirements.

Are you mounting the wing below the roofline?

What I like about the rear-end mounted bracket, such as those you have now, is how it situated the wing 6" rearward, effectively putting more leverage on the chassis so to speak.

I wonder how far back you can mount a 3D airfoil like GTC-300 and have it still function properly...
Or do you use a straight foil once you're really far past 'trunk mount' range (what a 3D airfoil is designed for afterall)... but i suppose it depends on height too...

ZX-Tex

iTrader: (15)

The main reason I went with the rear mount is that I plan to add a diffuser later on, and the low pressure zone under the wing augments the performance of the diffuser.

There is a downside to using leverage to weight the rear axle more. It also unweights the front more than if the wing was mounted closer to the rear axle.

GT42R

Indeed, but if you're getting that heavy into the rear wing game, you should definitely be addressing front aero as well.

I have a tubular front frame/rad support, that all my coolers hang from, as well as a very strong front splitter mount, so in my particular case I think I can take advantage of the leveraged wing out back.

ZX-Tex

iTrader: (15)

Front aero is already in place. I have a DIY air dam and a big splitter, also well mounted. I can stand on it in fact.

GT42R

So emilio posted this pic of new 2D APR wing with custom bumper mounting.

This is EXACTLY how I plan to mount my GTC-300; I'm going to build a tubular section off the rear frame rails and bolt up-rights through the bumper skin into the tubular frame underneath. Going to keep it pretty low though.

dgmorr

iTrader: (4)

Is this the same Crawford wing you guys are referring to?

http://www.casc.on.ca/forums/showthread.php?t=24740

Handy Man

I'd give Emilio a call about the mounting location of the 3d wing. I talked to him before making my custom risers and he had some great info about how high to mount it, and how it will effect your AOA.