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mrbigport
15th February 2011, 08:21 PM
Ok guys....don't knock it before you try it. when I built this I had my doubts, but the next track meet I picked up 1.1 seconds around the QR sprint circuit, so something was working, and the times have only got better since.

Enjoy

http://www.youtube.com/watch?v=z8NDuIXqSZo
<iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/z8NDuIXqSZo" frameborder="0" allowfullscreen></iframe>

http://www.youtube.com/watch?v=z8NDuIXqSZo

Adsie
15th February 2011, 08:26 PM
Haha I remember seeing this when I lined up behind you at QR thinking WTF, but if it works for you.

mrbigport
15th February 2011, 08:28 PM
when ya gonna come back?? open sprints ftw

blake.
15th February 2011, 08:53 PM
haha thats mad.

Gunner
15th February 2011, 09:49 PM
haha sick, wheres the rest of the info? How have you done it, hows it work?

Adsie
15th February 2011, 11:18 PM
when ya gonna come back?? open sprints ftw

Soon hopefully, had problems with the car but thats sorted now so just need to put interior back together.

blair
16th February 2011, 12:13 AM
How is the "active" part of it activated man?

Does it change angle with speed, if so, does it have an electronic controller with a speedo input or something?

Or does it have a super sweet cable from the cabin lol

looks like fun

mrbigport
16th February 2011, 12:22 AM
ok some info...

the wing is constructed from 0.5mm aluminium sheet with a poly tube chord and bonded balsa ribs.
the end plates I designed in autodesk inventor and had laser cut and cnc bent to shape.
the motor is a high torque servo motor normally used as the throttle control motor on a large marine engine fly by wire setup
the motor has moveable limit switches at each end allowing the max and min angles to be changed between runs (soon to be adjustable on the fly)
the wing is switched off the brake light switch, its a little crude but effective.

because the wing has a surface area of nearly half a square meter when vertical, the drag is definitely noticeable but more importantly the car is much more stable under braking.

I'm not saying its perfect, its not. the aerofoil has irregularities, the motor needs to be faster, and i need to wire up an intermediate position for high speed corners as I found i can take turn 1 at QR under full acceleration at the top of 4th if i use a small amount of left foot brake to bring the wing on.

It was a bit of an experiment and it seems to be working. its far from one of the aeromotions mega-dollar setupsbut for a weekends work and $100 its a good start

mrbigport
16th February 2011, 12:38 AM
the basic way it works is this...

when there is power to the motor it tilts the leading edge of the wing up until it hits the limit switch, this is the wing level or minimum drag position. since the motor is gear driven, trust me its not moving once its engaged.
when i hit the brakes the brake light circuit reverses the polarity of the motor and it tilts the wing to the maximum tilt position until it hits the second limit switch.
when i release the brakes the motor reverse polarity again and returns to wing level position.

xero
16th February 2011, 11:24 AM
have you tested your car with a non-adjustalble aerofoil to see what the results would be?
IE steal some towel rack off of someone, set it to the optimum position and hit the track again to see if the gains were down to the adjustable aerofoil or just having something on the back creating rear downforce.

looks good for a weekends work and a few $$$, would be good to see if you could set it so when your braking it works similar to that of the veyron :)

mrbigport
16th February 2011, 11:30 AM
thats pretty much what it does.
Under braking it goes to about 80 deg so it is pretty close to the veyron setup

mrbigport
16th February 2011, 11:35 AM
next track day I'll do a session with it fixed and compare lap times

Gunner
16th February 2011, 02:51 PM
Now I'm probably letting too much of the mad scientist in me out, but if you could run through a G meter, so x amount of gforce, in y direction equates for z amount of degrees at the wing? (no more left foot braking in high speed sweepers) I don't know anyway of doing such a thing, but I think it would be a really cool way to do it.

mrbigport
16th February 2011, 03:13 PM
It is doable,the accellerometer that im looking at does left right forward and back and is only $20. but at the moment i dont have the full proportional controller hooked up, and thus why im running the limit switches

Gunner
16th February 2011, 04:29 PM
ah k cool, interested to see your progress with this mate, keep us updated.

DX20VT
25th February 2011, 09:09 PM
When I changed the wing on my KE70 from a wee boot spoiler to a large high mount wing, I gained 1 sec per lap on a 1min 10 sec track.
And that is fixed position.
Adjusting it does have a big effect too.
It mainly helps on the high speed corners
and coming onto the main straight with more speed through the last corner.

So it shouldn't just work under braking, should also work under acceleration out of corners.

Basically the only time you dont want it right up is fullpower and in a straight line, the rest of the time it should be up.
Maybe try a micro switch on the acellerator so at full throttle it's down flat and up the rest of the time??

xero
28th February 2011, 02:07 PM
yeah but when are you not flat on the throttle in an N/A car?

mrbigport
28th February 2011, 02:49 PM
Semi slicks, 845kg wet weight, and sorted suspension keep things under control on corner exits, generally speaking a little bit more mid corner downforce would be good, and thats what I'm working on next.
but as a whole, when you only have 88kw maximum to play with you want to minimize drag. as much as an increase in mid corner grip would help, I'd be better off with an extra 5km for the length of the straights than I am with an extra 3kmh for the length of the corners. know what I mean??
I'm already as fast or faster than most through corners, but on the straights I get hosed. (bring on the boost)

DX20VT
28th February 2011, 05:53 PM
yeah but when are you not flat on the throttle in an N/A car?

the car is always limited by either sideways grip or forward/reverse grip, not usually both at the same time,
ie you are usually hardly ever still at 100% throttle and 100% of sideways grip.

If your limited by sideways grip you probably wont be at full throttle and the wing will help, otherwise it is drag.
If you limited by forward momentum you will be at 100% throtle and the wing wont be any use,

so how often you are at full throttle doesn't matter.

If you are at full throttle 80% of the time you only need a wing 20% of the time,
or lessactually as braking in a straight line the wing wont be required for downforce but the drag can help slow the car.

mrbigport
29th March 2011, 11:18 AM
The car is getting completely rewired at the moment since I'm wiring in the microtech for the new engine. I have a 3 pos switch for the wing so I can run either fixed or active or off...if I want to get really tricky I'll wire the fixed setup to a mid position and flick to it for high speed corners...but ill just get it working for now

As for the need for downforce under brakes...it helps immensely as you can brake more with all 4 wheels as apposed to unweighting the rears and locking a wheel.

DX20VT
29th March 2011, 06:45 PM
As for the need for downforce under brakes...it helps immensely as you can brake more with all 4 wheels as apposed to unweighting the rears and locking a wheel.

Yes that would make sense too,

Hachi_Tom
8th April 2011, 08:07 PM
i saw this today (was in the red, loud as fuck hachi next to you at the lights) car looks cool, definitely different hahaha.

mrbigport
8th April 2011, 09:24 PM
I'd just been to top rpm getting the microtech tuned...they got a laugh out of the wing lol