mrlegoman

There was a couple of threads going on about aero dynamics on the EG hatchback, [edit] found one of them:
https://honda-tech.com/forums/road-racing-autocross-time-attack-19/real-working-wing-options-searched-1577937/

I'm currently spending some time installing a front splitter from Special Projects Motorsports (KIWI) and also playing around with some undertray ideas. The car is ***-happy as is it now, so that is only going to get worse. So some downforce on the rear is going to be needed. The duckbill is not going to cut it, but the 1200$ J's Racing wing is a little out of my budget.

Anyway, I ran into this thread on another forum:
'93 Civic aerodynamics test
http://www.cleanmpg.com/forums/showthread.php?t=2854

One of the interesting diagrams was this one:


wannabeclean"What I found out by viewing the video, is that certain areas that I thought would behave a certain way actually did quite the opposite. In the image above, the blue areas were areas where that there was little to no movement in the yarn (the air was stagnant)

Areas in green were areas that had a vacuum to them - and pulled the yarn inwards much like the area around the windshield wipers.

Brown areas were areas where there was the most turbulence. The yarn spiralled in these areas."

So I started thinking about the trend of the mid-spoiler for the EG's and whether or not it would actually help create any noticeable downforce.




Does anyone think this is a legitimate option for rear downforce? Or stick with some sort of shopping cart wing design on the back?

TunerN00b

I think the gain from the "mid wing" (its a spoiler, not a wing BTW) would be mostly from moving the separation point back past the chassis. This can reduce drag and rear lift, if done right.

To generate real downforce, you want the wing in as open air as possible, meaning above the roof line and out past the sides of the car (if your rules allow).

Of course, more knowledgeable people than me might know how to phrase that better, or offer a different opinion. Good luck finding your answer.

mrlegoman

Post edited, thanks for the correction. My one concern is that I highly doubt the makers of these mid spoiler have actually done any wind tunnel testing with their product and are made purely for show. Since most of the kits "can be mounted with included double sided sticky tape", I know for sure it does not create a lot of downforce. But if they do reduce drag, then it may be something to look into. Hopefully someone knowledgeable can chime in.

dirty19

iTrader: (1)

Don,

Johnny Mac is an aero guru... Juan Tushag aka Renan, might also be able to put in his .02 along with some others.
It would be interesting to know what you can run to make the A** end settle down, plant and give you more bite.
Have you run the splitter from SPMS yet?

You are still running time attack only right?
I keep forgetting to send you the pics I took of you at Buttonwillow.
I have your addy I'll get on it soon.
Paul

turboteener

Save your money and buy the wing. I can get you a 68in wide GT/Trans Am style wing. Put one on a GTU/GT2 RX7. Calculations showed it would generate 450+lbs of down force at a 12deg AOA. The first lap out the car was lifting the front wheels enough the car was unstable and the driver complained about it. Even at half the angle of attack we had to build some winglets for the front to balance the car out.

With the true wing on the back of the car, you can set it up loose for low speed turns and the wing will stabilize the car at high speeds.

JuanTushag

agreed a real wing is what you need.

This last weekend at Willow springs there were 3 cars running the wing that i myself designed and tested.

before going through the drama of designing a wingI looked around for a wing to just purchase , but most commonly available were either too draggy or didnt come with any kind of data ( angle of attack settings etc )

I have worked designing wings for several years and the one I made comes with data showing downforce, drag and horsepower required ( given in 10mph increments, and at every angle of attack to be used , compensated for temperature and altitude ). The wing makes downforce from -2 degrees to +9.

I have been making them for the Honda Challenge guys for my cost which is around $400. Each is hand made, I am hoping to get them mas produced for a much lower cost, but that is around 3 months down the road. Pm me if you need one , I should have 2 more done by next Friday

mrlegoman

The front traction bar is currently in the shop getting rewelded to fit the SPMS splitter brackets. That is what has brought my concern about the rear. I'm squirrelly now. So with the new front splitter, I'm concerned about how much worse the rear is going to get.
Still just doing time trials and time attacks. So (for now) the rule books are still pretty open as to what I can do. Main thing is that I don't want to be pushed into an unlimited group. Even now, Redline is getting some high end teams in there and as a weekend warrior, I just can't compete with their budget.
Get me those pics!!

mrlegoman

Currently in the process of buying this setup:

The brackets are from Kiwi at Special Projects Motorsports. The wing is a Cwest GT Wing II Aluminum Single Flap. But I'm not sure if Cwest has any downforce data available. I know a lot of those wings are made for show with no actual test data to back them up. Once I have the brackets to fit the EG, I will definitely be interested in learning more about your wings. Do you have any links to pics and more info?

Tyson

i think youre in the right process of trying to deal with the not so aerodynamic shape of a wagon. the EF hatch is even worse off, especially compared to the CRX. aero drag isnt just the cross-sectional area, but more importantly whats going on behind the object in the wake.

my mind has already been cranking on that type of wing setup you just posted. but also to utilize those vertical supports as aero strakes, much similar to the rear end of the tractor trailer in the link you posted. if you can space those out properly, you can still use them to reduce the drag due to the air going around the side of the body. as you can see from the tufts you showed above, there is room for improvement. even that guys experiment above showed some improvement. stuff like that may look funny, and you dont see much of it in other "race cars", but why not think out of the box, especially in aero.

anyway, aero isnt a huge priority for us now. and its hard to test. its easier to just go with the advice already given and just slap a wing on it and ignore the rest. but the way i see it, theres room in the rules for improvement, it shouldnt just be disregarded. so i like your thinking too.

JuanTushag

your c west wing will probably work just fine for what you want to do . just be sure not to use too much angle. the one in the picture looks like it way exceeds its critical angle of attack.

to check it , take a end plate off,, then using an angle finder measure from the front tip to the trailing edge tip. first try 0-2 degrees angle . if its not enough try around 4. I wouldnt go up much more than that.

jt

JuanTushag

I will find and post some pics of the wing and angle finder i use
JT

.:Made in OC:.

Im currently running custom PC-I wing brackets and APR GT-U deck with custom end plates. The wing is stiff and produces enough down force to my liking.

I ran the car at BW without the front splitter and wing and the car was horrible unstable and lifted during corners as well as getting wiggly at high speed sweepers. After slapping both on, my car felt neutral again.

Renan (JuanTushag) & another aerodynamacist friend of mine took a look at my bracket + deck design and told me it it looked to be a good design and should work well for the car since the deck does have a good amount of angle at the trailing edge while zeroing out the angle of attack.

If anyone is interested in these PC-I wing brackets, please contact me and ill get them made for any hatch.

-Charles

jdm civic 2000

PM'ed.

JuanTushag

Hey Charles, your car looks really nice in that pic.

It looks a lot better than where i have my wing.

I have seen thoes brackets, they are really well made

NTCustoms

as stated earlier, those brackets are killer. well engineered, great quality. when paired with the APR GT-U or the C-west single deck, you're lookin at some noticable downforce. i'd bet with renan's deck you'd see something as well.

-Henry

slow_tortise

Hi. Im interested in the setup too. Could you hook me up with someone who sells them?

Also, would you know if the brackets allows the setup to be easily removable? such that if i use it on my daily car, i can just attach it on during track days, and then removing it when using on the roads.