Aerodynamics ... downforce, drag and all that JASS

[#Rotor]

Here is a sneak at what I'm busy with....

Personally, this kind of thing, on a normal road car.... you won't catch me dead in it.... But on an EXO... As far as I'm concerned, it really should not be without one of these babes....

http://farm4.static.flickr.com/3164/2388598417_a553f188a9.jpghttp://farm4.static.flickr.com/3220/2388598127_80889c55f6.jpg

This particular design, trying to be as generic as can be, wing height is a function of the length of the rods, 3 quick-change setting for pitch, and with the infanite adjustability gained from using Left-Right Rod-ends on the adjuster bars... The wanabe racers ultimite dream wing.... :coolnana:

Yeah right.... :D

[Karlo]

Rotor

Make sure you make it available for the other types of ExoCars also. :nod:

I wonder how you can make it universal looking at the Superlite Roadster below.


http://i188.photobucket.com/albums/z302/landfalcon/DSC02995Small.jpg

[#Rotor]

It's like you are reading my mind. Being generic is exactly why I chose the linkage method. Now the only part that needs custom fabrication, is the brackets that attaches to the car itself. The rest is all the same....

http://farm4.static.flickr.com/3031/2383152907_f4a71c4a01.jpg
At first, as you can see, I had a Laser-cut bracket all the way up to the wing.... very expensive and not generic at all....

With the linkages it's much easier to choose different wing heights. just by having a couple of sets of them, lower the wing all together for high speed long sweeping tracks.... Or put the wing right up there for those short slow and twisty tracks, easy as 8 bolts....obviously with 100% adjustability still intact.

[Steve Jarvis]

I definitely want a rear wing, but these cars are not going to need that much rear down force without a front wing. So, we need a front wing as well. :)

I know, we can take out as much down force as necessary by reducing the angle of the wing, but a front wing would look cool. :)

Later, Steve

[Karlo]

Another mounting option

http://i188.photobucket.com/albums/z302/landfalcon/DSC02983Small.jpg

[B-T]

My thought is that at high speed the SL-R may have a tendency for front end lift without some aero help. The bottom pan of the car can act like a big splitter and the drag of the top of the car will tend to rotate the car up. I would think the front would benefit from some small attachments like they have on the Viper track cars. I forget what they refer to them as, but they project maybe 1" or so from the side and are angled down about 30-40 degrees along the sides of the nose cone or the pedestal between the nose cone and the lower splitter.
The rear wing is a cool, good looking idea, but not nearly as important as front end downforce in my opinion.
BT

[soon_2b_evil]

Another mounting option

http://i188.photobucket.com/albums/z302/landfalcon/DSC02983Small.jpg

hey is that a intercooler or a oil cooler over there by the left wheel?
Oh yeha some front down force would be Great!

[Craig – Absolute PACE]

You've got an eye for detail.

Yes, that's an intercooler. There is also one on the other side.

It's a twin turbo lexus setup, developed by ozvenom. The same guy that is building our first track SL-R. He is a genius at fabrication, although so far he has been a bit disappointed by the easy bolt together nature of the SL-R. At least he can use his skills on the wiring harness and aftermarket ECU and all the go fast mods for the 4G63.

Here is a better photo.

http://racecarreplicas.com.au/photos/RCR_SL-C_Twin_Turbo_Lexus.jpg

[#Rotor]

now That gearbox, what is it from? Should be more than good enough for 600BHP right?

I'm looking to have it run on a 20B rotary motor, that I can mount lateraly in my design.

[soon_2b_evil]

You've got an eye for detail.

Yes, that's an intercooler. There is also one on the other side.

It's a twin turbo lexus setup, developed by ozvenom. The same guy that is building our first track SL-R. He is a genius at fabrication, although so far he has been a bit disappointed by the easy bolt together nature of the SL-R. At least he can use his skills on the wiring harness and aftermarket ECU and all the go fast mods for the 4G63.

Here is a better photo.

http://racecarreplicas.com.au/photos/RCR_SL-C_Twin_Turbo_Lexus.jpg

wow that looks really nice. Twin V8 lexus motor? yeha im turbo head deep inside and i notice stuff like that! LOL yeah I havent placed a order for a SLR yet but ive got the plans on building a turbo K24/k20 in it already. I love welding and building stuff like that. Ive already fabricated how everythings going to work out. LOL we all know its not that easy tho and not all if its going to actually work out till its here! LOL Cant wait to build a exhaust manifold for it!

Also i was going to go with the 4g63 setup but then i relized the turbo is going to be right behide the seats! idk about that part! LOL

[B-T]

How do you fabricate how everything is going to work out if you don't have any frame data for clearances etc...? I can tell you that the non-turbo K20 motor fits but there is not 'unlimited' space all around it for turbo piping etc...
BT

[soon_2b_evil]

How do you fabricate how everything is going to work out if you don't have any frame data for clearances etc...? I can tell you that the non-turbo K20 motor fits but there is not 'unlimited' space all around it for turbo piping etc...
BT

LOL ive just been running ideas thur my head looking at pictures! LOL I havent started on anything. just thoughts!

[B-T]

Okay, I thought maybe you were a welding savant! Not as common as the math or music savants, but I'm sure there are some somewhere...
:run:
BT

[soon_2b_evil]

Okay, I thought maybe you were a welding savant! Not as common as the math or music savants, but I'm sure there are some somewhere...
:run:
BT

LOL! actually spent a good hour on RCR site looking at the concept version and running thur a turbo setup in my head about how to run things on it actually. Sorry when i get excited over something it takes alot to get me to stop! LOL Even tho i havent even gotten one yet. I was going to wait till X-mas to get this but i might have to do it sooner!

[Craig – Absolute PACE]

Yes, with the 4G63T in an SL-R will have the turbo next to the firewall. We will just fit some good heat insulation, look at burst protection etc and it will be sweet. Because it is an open car, heat won't be an issue anyway.

For us the new generation NA & turbo Mitsubishi engines are just about perfect.

Check out 2008 Lancers they have 4B11 engine in both NA & turbo form. The larger fwd cars have 4B12 engine.

These are all aluminium, DOHC, MIVEC and best of all they have the intake & exhaust reversed. So on an SL-R the intake will be next to the firewall and turbo at the rear.

Mitsubishi 4B11/4B12, a sweet engine choice in my books.

[Chadillac]

The 4B11T does look like it's going to be a very good engine. I lot of the evo X guys are getting some pretty good power out of them with just simple bolt ons. I guess the engine comes with a pretty bad tune out of the factory. And with the engine being in several different cars (evo X, lancer RalliSport, kia, hyundai) the aftermarket is going to be crazy!

[Craig – Absolute PACE]

Yeah, it's certainly looking like a worthy successor to the 4G63T.

Even better is it's suitability for the SL-R.

[ozvenom]

The idea of down force is good but i has to be applied in the correct location. ie if mount the rear wing behind the rear axle centerline it put force down on the chassis but also will leaver the front up which will cause all sorts of problems most race cars get away with this because of the down force created at the front of the car .
so idealy the wing should put its load over the axle or slightly in front of it. also having good front down force is very important .
oz

[#Rotor]

Some updates


http://farm4.static.flickr.com/3047/2516902284_14333695e6.jpghttp://farm4.static.flickr.com/3140/2516101033_bc58ccda23.jpg
http://farm3.static.flickr.com/2283/2518199058_76269274d0.jpghttp://farm4.static.flickr.com/3189/2518201204_b6ee94e152.jpg

allmost done with the wing itself, still waiting on the brackets, that is being lasercut for me.

[B-T]

I like the look of it! I will probably just order a prefab wing and get some struts made up to bolt it to the hoop supports on the SLR.
BT

[Karlo]

Carbon looks great :thumb2:

[#Rotor]

thanks....
:)

I just love that holographic property of a nice shiny piece of it, when you hold it in the sun...

[Craig – Absolute PACE]

Excellent work. :thumb2:

Yeah there is just something cool about carbon fibre. :)

[#Rotor]

got all the scafolding together earlier.....
http://photos-c.ak.facebook.com/photos-ak-sf2p/v248/250/37/678048646/n678048646_638250_9461.jpg
http://photos-a.ak.facebook.com/photos-ak-sf2p/v248/250/37/678048646/n678048646_638248_8930.jpg
http://photos-b.ak.facebook.com/photos-ak-sf2p/v248/250/37/678048646/n678048646_638249_9191.jpg

I'm pleased with it's rigidity, not bad for it's overall weight.

[Karlo]

Looks good!!

[Chadillac]

I like it too. Is it possible to adjust it once it is mounted? It would be pretty fun to play with the angle of attack to see how it effects down force.

[#Rotor]

ou yes... very easy to change... I have 3 settings to choose from... and then I can alter the rod-leghts as well....

[#Rotor]

here is an update....

http://farm4.static.flickr.com/3089/2865117630_5d60d08ef9.jpghttp://farm4.static.flickr.com/3097/2864285943_0a0839445a.jpg
http://farm4.static.flickr.com/3080/2864285709_82f5d9a291.jpg

I never thought it could make such an massive difference to the way the car presents itself....

[Karlo]

Proportional the wing looks perfect good work!!! How does it feel?

[#Rotor]

I am very pleased with the wings rigidity. And yes, was a bit concerned with the size and shape of the side plates.... but as soon as I installed it, it looked perfect, not too high, not too far back, not too wide.... just perfect....
Some nice shots....
http://farm4.static.flickr.com/3099/2866839309_e403c10a92.jpghttp://farm4.static.flickr.com/3124/2866838987_1ebb20af70.jpg
http://farm4.static.flickr.com/3187/2866838345_d467442747.jpghttp://farm4.static.flickr.com/3028/2867670220_1d5aaf6228.jpg

[Tyoneal]

To All:

There are a couple of excellent Books on Race Car Aerodynamics you may want to read or at least go through before spending a lot of money on parts that may not accomplish your intended task.

One is:

"Competition Car Aerodynamics", a Practical Handbook

by Simon McBeath

http://www.amazon.com/Competition-Car-Aerodynamics-Practical-Handbook/dp/1844252302/ref=sr_1_3?ie=UTF8&s=books&qid=1231580834&sr=1-3
====================================
another is:
====================================
"Race Car Aerodynamics: Designing for Speed" (Engineering and Performance)

by Joseph Katz

http://www.amazon.com/Race-Car-Aerodynamics-Engineering-Performance/dp/0837601428/ref=sr_1_1?ie=UTF8&s=books&qid=1231580729&sr=1-1
=====================================
..... and Lastly for the Hardcore among us.
=====================================
Race Car Vehicle Dynamics

by William F. Milliken (Author), Douglas L. Milliken (Author)

http://www.amazon.com/Race-Vehicle-Dynamics-William-Milliken/dp/0768001218/ref=sr_1_5?ie=UTF8&s=books&qid=1231580966&sr=1-5

Not Cheap, or for the faint of heart, but an absolutely Top Notch Comprehensive look at Race Cars. (Brush up on your Math, or at least your understanding of it before getting it)
=======================================
The links all go to the Amazon page where each can be found.

Hope this helps,

Ty O'Neal

[Gage]

Look.. if you want an aerodynamic light weight car:

http://www.reynardracingcars.com/reynardA4brochure.pdf

[CMC#5]

Rotor, what software are you doing for that work?

[#Rotor]

all my stuff is done with Auto-Cad. I use Solid works for Some FEA. and Virtual Wind-tunnel for the wings and body parts.

[Tyoneal]

Look.. if you want an aerodynamic light weight car:

http://www.reynardracingcars.com/reynardA4brochure.pdf

Gage:

Very cool find. Heck I'd pay $50 for a ride just to experience a 4G Turn!

On second thought I guess it would cost me $100, as I'd have to do one in the other direction to swing my face back around so I wouldn't be sneezing out my ear.

It would be fascinating to see what that car would cost. Given who made it, I bet it's as expensive as hell.

Thanks for posting it.:thumb2:

Ty

[bolus]

I call shananagans. I doubt those A048's could take 4000lbs of lateral force. I would need to see the sustained g's on a accelerometer to believe it. And not when the car hits a bump and the g meter jumps for an intant. :)

I see the Radical listing as pulling a little over 2 g's and that has similar aerodynamics.

SHANANAGANS! :)

[Tyoneal]

I call shananagans. I doubt those A048's could take 4000lbs of lateral force. I would need to see the sustained g's on a accelerometer to believe it. And not when the car hits a bump and the g meter jumps for an intant. :)

I see the Radical listing as pulling a little over 2 g's and that has similar aerodynamics.

SHANANAGANS! :)
==========================
Bolus:

I tend to agree with you.

Are you another South Park afeccionado? (Those who don't understand don't worry about it?

You would think a Race Car Building Company would know how to check and be honest with their evaluations. That's the main reason I would be excited to give it a go, but 4G's? Holy Ca Ca Batman that's some serious force.

Ty

[cordycord]

If you dropped it on its side, you'd get WAY more than 4g's. Otherwise, shenanigans.

But back to the topic at hand. the wing end plates make a big difference in efficiency. They may not add to the aesthetics, but they do add to the downforce.

[ozvenom]

After have run the slr on track it would seen that rear down force is a low priority but they do need quite a bit of front down force to keep it pined down and the car stable.
oz

[Fran Hall RCR]

Scott,

once heavier springs were installed, and suspension settings played with ...camber/toe etc etc .. the attitude of those big tyres was more controlled ...the front lift (rear squat) the weight transfer was no longer an issue...the Mitsu with all the gubbins mounted was heavier than I anticipated.

Front aero is a non issue ....yet!!!...the car has far more potential and is already running at FTD with the V8 monsters...once the times level off, its time to make changes but development needs to be done one step at a time or confusion sets in....

[golftdibrad]

I call shananagans. I doubt those A048's could take 4000lbs of lateral force. I would need to see the sustained g's on a accelerometer to believe it. And not when the car hits a bump and the g meter jumps for an intant. :)

I see the Radical listing as pulling a little over 2 g's and that has similar aerodynamics.

SHANANAGANS! :)

You'd be surprised how much downforce you can get out a diffuser that is not restricted by the rules of a governing body. If it can really drive on the ceiling at 100, i bet at 150 with race slicks its pulls 4g's

Here is a sneak at what I'm busy with....

Personally, this kind of thing, on a normal road car.... you won't catch me dead in it.... But on an EXO... As far as I'm concerned, it really should not be without one of these babes....

http://farm4.static.flickr.com/3164/2388598417_a553f188a9.jpghttp://farm4.static.flickr.com/3220/2388598127_80889c55f6.jpg

This particular design, trying to be as generic as can be, wing height is a function of the length of the rods, 3 quick-change setting for pitch, and with the infanite adjustability gained from using Left-Right Rod-ends on the adjuster bars... The wanabe racers ultimite dream wing.... :coolnana:

Yeah right.... :D

http://www.exocars.net/attachment.php?attachmentid=1778&stc=1&d=1240155949

in cars like these its fun to use banned racing technology. if you closely follow how the wing is mounted to this 06 FSAE car, it provides its download directly through the suspension links to the tires. This allows you to not have to set you spring rates and whatnot for downforce applied to the ground through the chassis (high wheel rates result from this setup). for a street car, this means a more forgiving ride but maintain great handling at higher speed.

This method is banned even in fsae now, one of the last creative outlets for racing design.

-Brad