Vortex generators

[BarkerMan]

Actually I don't drive like a race but I don't baby it either. Gasoline was better 30 years ago and I got better mileage. And with a few long trips I will better the 46. Actually the wagon has better aero performance than the sedan.

I it's ok I would like to make a suggestion. I have done a lot of experimenting with stuff and one thing that has worked is a vortex generator. I have some friends in the racing business and from time to time they ask me to get involved because even though I'm old and washed up they like the idea that I figure stuff out. Small vortex generators really work. They improve the aero performance in a wide enough range of speeds without out penality in a range where they are not effective. Here is a link where you can buy a set and they come with directions that are tested and produce useful results.
http://www.manufacturersdepot.com/ProductDetail.jsp?LISTID=800000A6-1180622063
http://www.vortekz.com/
If you look at the manufacturer's site they explain how to set them up, and for twenty bucks they are a good deal. One good part of the deal is that you can experiment with not only the fore and aft position but the angles and spacing and they don't stand out like a sore thumb like those big ugly wings that you see on some of these kids cars. Most of those wings are a neon sign that reads, "I'm and idiot".

 

[BarkerMan]

If there is any interest I'll tell you how to setup these vortex generators.

 

[gtx510]

I can remember seeing similar generators for bigrigs a few years back and I wondered how long it'd be before we saw thm on cars. Mitsubishi answered that question a couple years ago.

Did you put yours just in front of the hatch?
Have you seen the wagon "airfoils" that help keep the rear glass clean? I think someone was remaking those.

Do you think the generators would work on the upper wing of a 323GTX?
http://sturtevant.com/reed/323pics/323pete.htm
http://sturtevant.com/reed/323pics.htm


I'd love to hear more details about your engine and I'm sure most of the Bluebirds list would too.
What carb do you run? Hitachi? SU's?
I'm guessing you've already done a 5-spd swap? 200SX dogleg, truck, Zcar?

 

[Master ACiD]

the only thing i would say is that at $2.00 a piece it is very expensive for what you get. it looks like just a piece of moulded plastic. perhaps you could even use one of those vacuum forming machines to make 20 at a time for a few bucks per 20.

 

[BarkerMan]

You need to figure it out on your car. In a vertical line from front to back along the centerline you need to tape tufts of very soft yarn, every six inches along the roof. Then you drive down a road and start at 30 and in steps of 5 miles per hour speed up with a car along side and watch the yarn. If the flow is smoother the yarn will trail back pretty close to the body. Use the front pieces as a guide. Where the air separates the yarn will not fold back the same as the pieces in the front. Pick a target speed and watch for the separation. At this point re tape the yarn at closer intervals and overlap them by spreading them over the width of the car. Recheck and mark the spot. Then follow the instructions with the vortex generators and use their template. If you take the time they work. You can paint them the color of your car so they don't stand out. If you are not into experimenting and already know that they don't work then skip the whole thing. And if you think that getting the right size and shape vortex generator is not worth twenty bucks then you should extend the experiment and design you're own. I did and went back to the ones in the link after a day of experimenting. It's possible that I wasted enough gasoline that day to cover any advantage for quite a few tanks of gasoline. But I enjoyed the experiment all the same.

 

[BarkerMan]

Oh by the way, you can improve your mileage with that 323 by ditching the roof rack except when you actually need it.

 

[speedyswede]

BarkerMan, I already have purchased & installed a set of Vortekz generators on my nephew's IROC Camaro. I bought the primed version and had the professionally painted to match his car.
Overall, I was rather impressed with the quality of materials. They're not plastic, they're polyurethane. They're kinda flexible, so you'll need a flex agent if you want them painted-to-match. The lazer-cut 3M adhesive pads fit perfectly and hold very securely. I had 'em installed on his car in about an hour...taking my time. He likes 'em a lot...but claims that he gets questions about thier function almost everyday.
I won't install them on my cars...Both of my cars are "two-box", square back vehicles. I think the Vortekz fins serve more function on a sloped-back sedan or fastback coupe.

 

[Shannow]

Originally Posted By: Master ACiD
perhaps you could even use one of those vacuum forming machines to make 20 at a time for a few bucks per 20.


My vacuum forming machine is busy right now.

How 'bout you knock me up a set of 20, and I'll give you $15.

 

[Gary Allan]

Don't know what they'd do for the Wrangler. I tried a quick change air dam for the front to reduce air under the vehicle. It didn't do squat. It was a failed experiment. Maybe I can put those just off the leading edge of the hood ..in an attempt to move some air around the windshield.

 

[speedyswede]

Originally Posted By: Gary Allan
Maybe I can put those just off the leading edge of the hood ..in an attempt to move some air around the windshield.

I doubt that'd work either, Gary. Vortekz fins are based on Mitsubishi's concept to simulate laminar airflow in an area where gradual air separation would normally exist...eg: the area behind the roofline on a typical sedan w/sloped rear glass.

 

[Gary Allan]

I don't think anything can improve pushing a brick into the wind..

 

[televascular]

An interesting product. I consider myself a function-before-form kinda guy, but...

My car has sleek body lines and I do not want to ruin it with these blemishes lining the roof like a spike strip. Unless it provides a 20% increase in gas mileage, this is where I draw the line.

 

[BarkerMan]

A couple of 850 Volvo wagon owners are experimenting with them and claim useful results.

 

[speedyswede]

Originally Posted By: BarkerMan
A couple of 850 Volvo wagon owners are experimenting with them and claim useful results.


Don't get me wrong, I like the appearance and potential function of them. But my Volvo wagon is already equipt w/ a high mounted rear lip spoiler on top of the hatch. Since the spoiler is already running in clean air, adding the fins in front of it would most likely be counter-productive.
And its kind of the same with my Wife's 2003 VW Golf. Her car has an OE hatch spoiler/extension to help reduce parasitic drag.

 

[BarkerMan]

They removed their spoilers that ran along the top of the tail gate on the 850 wagon and added the vortex generators and claimed an improvement and the rear window stayed cleaner, too.

 

[speedyswede]

Barkerman....not to be critical, but Mitsubishi's original tests indicated only a miniscule cd improvement on the Lancer EVO. So when you say that the 855 owners "claimed an improvement", what exactly do you mean?

The other part of Mitsu's tech sheet that I found interesting was how the original intention of the VGs was to intensify pressure on the EVOs OE rear wing, which they apparently did rather well.

 

[BarkerMan]

One 850 wagon owner claims that on his trips between San Diego and Phoenix and San Diego and San Francisco in his business he got a repeatable 1 mpg improvement done over many trips and lost it when the generators were removed and the spoiler put back on or no spoiler. He said he could not feel the difference either way and that with the generators during rain his rear window was cleaner. He also said that he experimented with the fore and aft positioning and said that they were very sensitive to the distance from the rear window edge. Another 850 owner is still working on the positioning and is experimenting with the angles of the outboard generators and is not putting them in a straight line across the roof. He said the difference is more than 1 mpg improvement over 70mph, under 50 he thinks they have to be in a different position to work. I hope I've answered your question. I think the answer so far is that they do something.

 

[speedyswede]

Originally Posted By: BarkerMan
He also said that he experimented with the fore and aft positioning and said that they were very sensitive to the distance from the rear window edge.


Very interesting, do you know what the results were when they were moved fore & aft and which position was more effective? :???:

Originally Posted By: Barkerman
I think the answer so far is that they do something.


...and I don't doubt that one bit.

 

[BarkerMan]

I think you have to try for yourself. That's the fun in an experiment.

 

[speedyswede]

After a few weeks of careful deliberation, I've decided to order the Vortekz VGs for my Volvo wagon. I may end up deleting my rear spoiler altogether, but I intend to keep it on for now and see how overall stability is affected.
Actually, I have 3 Vortekz kits on order. My Dad expressed interest in them for his Mazda5, so he's getting a set for his birthday(painted-to-match too). And one of my co-workers also wanted a set for his `99 Audi A6 Avant.
Thus begins my triple "two box" VG experiment.

I'll keep ya' posted.