Aero work, lets see it.

[tsirider13]

hey guys,
For this winter I will be working on aero for my car.
I do have a pretty good feeling of what I will going with, but I would like to see what you guys that have been racing longer have fabricated to make our cars a little more stable and eficient on road racing.

Post pics of what you have work so far and post tips for rookies like me, I will do the same when I have advance more in my set up.

Thanks.

 

[dsmfa9nutter]

I've done most of the following, basic guide and a couple really good links.

Lower it (obviously).
Front and side air dams to reduce the gap between the body and the ground, you want the least amount of air going under the car as possible.
Front/rear diffusers.
Underbody smoothing, get out the tinsnips and some sheetmetal and fab up some flat plates to cover any large open areas under the car.
Ducting on the front of the car, make the air go from flipping around in your engine bay to cooling off your brake ducts/oil cooler.
Fender/hood vents to get rid of the air that does get into the engine bay, this will cool off underhood temps as well.

http://www.dsmtuners.com/forums/roa...-working-aero-front-done-now-i-need-wing.html

Race Car Aerodynamics - Designing for Speed  -  Bentley Publishers - Automotive Books and Repair Manuals
Vehicle Aerodynamics

There's individual vortex generators out there. I know a hundred and one people will bash them but they do work (at higher speeds of course). I've had my car to a buck fifty with and without them and there is definitely a difference (2000lb hatchback). When placed properly, they trip the airflow from laminar to turbulent to keep it attached over a surface, thus reducing the dead wake and the drag. Really spiffy bits that work well when used correctly.

 

[gixrman]

There's individual vortex generators out there. I know a hundred and one people will bash them but they do work (at higher speeds of course). I've had my car to a buck fifty with and without them and there is definitely a difference (2000lb hatchback). When placed properly, they trip the airflow from laminar to turbulent to keep it attached over a surface, thus reducing the dead wake and the drag. Really spiffy bits that work well when used correctly.

They don't work on the eclipse body style because there is no sharp seperation in the flow line over the body. On your colt and the EVO yes.

 

[dsmfa9nutter]

They will work on a DSM, their placement will differ and the effect will be minimal. On an all out aero car, every little bit helps. Doesn't hurt that they're cheap off ebay either.

 

[pneumo]

They don't work on the eclipse body style because there is no sharp seperation in the flow line over the body. On your colt and the EVO yes.

I agree with this for the smoother 2G body style, but it may not be true for the 1G.

I did some tuft testing on my 1G and found that airflow detaches and becomes turbulent about halfway down the rear hatch, but only along the centerline of the hatch. Air flowing along the sides of the hatch remains smooth, although the air is flowing inward from the sides at about 20 to 30 degree angle. Overall there's a turbulent area approx 2.5 feet wide at the base of the hatch which begins at a point approx 6 to 8 inches behind the rear window washer nozzle.

Another tuft test I did showed that in the area of the rear wing, air is turbulent at over 6 inches above the center of the rear deck, so if you want to install a rear wing, I'd mount it at least 8" above the deck, if not more.
HTH