drag racing aero help

[gillard26]

Hello.

WE are currently drag racing a mazda rx7 fd3s. The body style of the car is based on the veilside combat 2 body like the one in the link attached. the only differance is the rear wing has been removed.

We need to imporve the cars aero perfomance and add some high speed stability. the taget speeds are in the 160- 170 mph region on 28 inch tall 13inch wide slicks (rear only)

http://www.the-blueprints.com/blueprint ... mbat-2.gif

Some guys run a flat rear wing like this. Im struggling to see how it helps
https://www.btowstore.com/WebRoot/BT/Sh ... _impey.JPG


Im looking for any help you guys can offer. The car is currently out of action for a while


Thanks

Scott

[Shrek]

I know that in NHRA drag racing, the flat wing (i think it's actually a spoiler, because there are no curves to it) is very common and i thought of this as why carmaker's and racing teams don't do it, by why not make the radiator intakes feed from behind the wheel in the wheel well, you might barely increase drag from the wheelwell, and you'd lose all/most of the front grille area (use tape(cheap version) or a reducer of some sorts or go all the way and redesign the radiator inlet) so you'd have less drag note this might be very costly

get rid of the front and rear windsheld wiper mechanism, unless this is a daily driver, then just the wipers

if you can, put a diffuser/a simple bellypan on the underside of the car to where it meets the front bumper at 90 degrees

Mirrors unless again a daily driver

I would remove the rear wing on the back of the car unless your having issues with wheelspin at the end of the track

[gillard26]

Thanks.

Yeah the wipers and the rear wing have gone along with the side mirrors. the car is only a drag car so we can be what ever with it.

I was thinking along the lines of sealing the front up as much as possible. The car is nervous at high speed due to many reasons but i would say mainly due to the low pressure in the rear tires. The main aim as per any car is to lower the drag but add stability at high speed.

Scott

[jddh1]

Are you guys able to test various wings? I'm thinking, if you have the cash to have 3 or 4 around and test the different profiles. Because it sounds like you, as Shrek says, are in need of some downforce at the rear on high speeds. I bet that with a decent wing you will solve a lot of your high speed stability issues.

If you can't afford testing the wings physically, then it would be nice to create a 3d model and run a CFD test. That would be easy if you have friends that do these things in school. It would be an extra project for them, which they may include in their portfolio, and for you it would be free.

I'll keep an eye on this thread for your progress.

[alelanza]

I know that in NHRA drag racing, the flat wing (i think it's actually a spoiler, because there are no curves to it)

They are curved,



even the pro stock cars i think, though i have not seen one myself up close

[gillard26]

Top draw. Good ideas guys. There is no reason why we cant back to back aero parts at all. Its just the manufacture. It would be worth following up that CFD idea and from my limit aero understanding i can see that nhra car wing is much better than the pic i provided.

Scott

[FCDatalogit]

Hi Scott,

I know its four years since this post but i'm wondering if you got anywhere with your serach for Aero help.
We too have a Rx7 FD3S drag car.

Cheers
Alice

[g-force_addict]

Hello.

WE are currently drag racing a mazda rx7 fd3s. The body style of the car is based on the veilside combat 2 body like the one in the link attached. the only differance is the rear wing has been removed.

We need to imporve the cars aero perfomance and add some high speed stability. the taget speeds are in the 160- 170 mph region on 28 inch tall 13inch wide slicks (rear only)

http://www.the-blueprints.com/blueprint ... mbat-2.gif

Some guys run a flat rear wing like this. Im struggling to see how it helps
https://www.btowstore.com/WebRoot/BT/Sh ... _impey.JPG


Im looking for any help you guys can offer. The car is currently out of action for a while


Thanks

Scott

Do rules allow you to modify the floor pan?
If so then add a flat section in the front and a diffuser in the rear even if that requires you to cut the rear bumper and trunk.
I'm pretty sure most road-racing aerodynamic mods would be quite useful in a drag race car. And there are plenty of such mods available for RX7s.

[strad]

You do not want any aero aids that add too much drag.
They get away with huge wings in the top classes because they have way excess power and travel 300MPH.