David Buschur

iTrader: (53)

Last year I became interested in trying to clean up the way the air moves around my RS. I was hoping to help the car go faster by making it cut through the air more cleanly.

I built a front undertray, diffuser and front block off plates for the fascia (all of which are available btw). I also added a vortex generator after seeing some interesting testing on them. It seemed to help as the car had some killer MPH at the track, running 159.64 mph at 2985 pounds on an HTA86 at only 43 psi of peak boost.

I had found some videos and read some articles on wool tuft testing. This is a process where pieces of wool or yarn are attached to a car and then video taped to see how the air moves around the vehicle. I bought some bright orange yarn, grabbed a roll of tape and our video camera and figured I'd go make some video.

For now all I have done is the rear of the car. Rear window, deck lid, wing, back of trunk lid/bumper and the underside of the diffusers we build with the EVO9 JDM bumper.

My findings are the vortex generator absolutely without a doubt has to help the car. You can see in the videos it keeps the air attached to the entire rear window and trunk lid. The wing you can also see has nice air flow around it.

It also appears as though the back of the EVO is pretty well designed as there is very little air attached to the trunk, which I believe is good as it seems the air is making a clean break from the trunk and sides of the vehicle.

It is also nice to see the diffuser we built is working as the yarn is layed flat against it and then breaks nice and clean on the edge.

Something else you will notice is the rear windshield wiper for sure disrupts the air on the back of the car.

In a few of the videos you will notice a piece of yarn close to the camera moving all over the place, ignore that piece, the air is being disrupted from the camera mount.

Anyway, it was interesting to me so I thought I'd post it up for others to see. Just something else in the never ending quest to go faster and faster.

I want to do the hood, front fascia and the undertray next but need to get the time and motivation to get to it.

Here's the video. It's my first ever video, Jarrod added the hippie music for me. haha

http://videos.streetfire.net/video/B...ero_684440.htm

Clutchdc5

iTrader: (1)

very imformative, thanks

srtboostin22

iTrader: (7)

good vid! nice music

scumrat

iTrader: (1)

whoa! what an awesome idea! great soundtrack also.I always liked watching aero test in the wind tunnel.Its amazing how many things there are that ALOT of people overlook in favor of apperance.Great job and awesome attention to detail!

Jrod@Buschur

iTrader: (101)

I thought the music went well with the video. Besides..... we are in Wakeman ya know, I could have used "Dueling Banjo's" instead.

David Buschur

iTrader: (53)

The music does go well to be honest, it is hippie music though! haha Thank you for putting it on there for me Jarrod. Sorry I didn't use your link, I'm at home, obviously you are too and didn't have it.

Glad some of you found it interesting.

JordanS4

iTrader: (11)

awesome thanks

EvoDan2004

iTrader: (94)

very cool vid. so as for the testing you did what would you say would be the best setup??

vg with wing and jdm 9 rear with under panel????

any plans to make a CF VG lol

also i know its ''rice'' but maybe try and find a junk rear bumper and put them holes in it and see if that ''para shoot'' effect is reduced or if it helps with less drag

Rocky2

at the music.

red03evo

iTrader: (20)

Good info.

EatSleepBoost

iTrader: (9)

+1. but in all honesty that was a good video to watch.

Smike

iTrader: (8)

This is good to actually see what the air is doing on and over the car. And nice to see the VG works even at lower speeds. One of the first things I noticed on my car post VG was how rain went down the rear window.

David Buschur

iTrader: (53)

Well since I can't measure the effect of the rear wing and the down force it is hard to say which is the best set up.

From the pictures and for drag racing, I am going to say a wingless, vortex generator with the EVO9 JDM bumper and diffuser looks really good and NO rear wiper. It looks to me like the air stays attached to the car and then breaks away fairly clean on the trunk, sides and the diffuser. This should make for the least drag on the car. If you needed some down force I'd have to assume Mitsubishi knows what they are doing and adding the stock wing to that would work out better, put the wicker bill on the stock wing for even more downforce.

On Project White after doing this testing I ended up with a Vortex Generator on the car with the stock wing. I also added our block off plates to the front fascia and a carbon fiber lip. I did those three changes and added drag radials to the car, no tuning and gained over 3 mph from the last time I ran the car. Also had Kevin behind the wheel compared to me the first time but in the past I have proven to have similar MPH to other drivers (ET just sucks). So I'd like to think some of those gains in MPH were from the cleaning up of the cars aero.

David Buschur

iTrader: (53)

Yes, that's for sure Smike, the VG works and it is noticable the difference in the rain instantly.

BTW, I used the actual factory VG on both of my cars, no cheap knock offs. Very easy to install.

SpinninAll4s

iTrader: (1)

Seems like with the VG/wingless flows air very well!