vortex generators

[Overkill Fab]

well i'm new to the Yaris and this forum so I will keep it simple. Read up on the VG's and thought I would give it a try. I have a 100 mile commute everyday and want to maximize MPG.
So I had some scrap 1/2"x1/2"x1/16" angle aluminum in the shop and thought I would try that first.
http://www.yarisworld.com/forums/att...1&d=1373130395
used 3M hanger double sided tape to attach themhttp://www.yarisworld.com/forums/attachment.php?attachmentid=51285&stc=1&d=13731303 95
marked off even spaces for a total of 12 VG's.
http://www.yarisworld.com/forums/att...1&d=1373130395
used a protractor set at 18 degrees for the correct angle. Somebody correct me if i'm wrong as that's what I read is the best angle to use.
and installed them.
http://www.yarisworld.com/forums/att...1&d=1373130395
This was just a first try as I soon found out this is a bad spot as the rear hatch hits them. Also not to sure there current location is effective as its after the break for the rear hatch and I may move them forward. Also may up the size to 1"Hx2"L. but this is what I had lying around.
noticeable changes? Not really but the rear end did seem more stable when cornering at speed.

[Idahotom]

I think you may want to move those forward. The picture I posted was my first spot, but then I moved them forward to right behind the antenna. The theory being the vg's need a little distance to effect the downstream airflow. Just a wild ass guess, no testing! But mine are now glued down right behind the antenna, In the aircraft world, somewhat the same deal, they are put a bit ahead of where you want the effect most. The good thing about the double sided tape is it's easy enoguh to try a few places, and yeah from a practical standpoint further forward is better re: hatchback opening!

[malibuguy]

Originally Posted by Overkill Fab

well i'm new to the Yaris and this forum so I will keep it simple. Read up on the VG's and thought I would give it a try. I have a 100 mile commute everyday and want to maximize MPG.
So I had some scrap 1/2"x1/2"x1/16" angle aluminum in the shop and thought I would try that first.
http://www.yarisworld.com/forums/att...1&d=1373130395
used 3M hanger double sided tape to attach themhttp://www.yarisworld.com/forums/attachment.php?attachmentid=51285&stc=1&d=13731303 95
marked off even spaces for a total of 12 VG's.
http://www.yarisworld.com/forums/att...1&d=1373130395
used a protractor set at 18 degrees for the correct angle. Somebody correct me if i'm wrong as that's what I read is the best angle to use.
and installed them.
http://www.yarisworld.com/forums/att...1&d=1373130395
This was just a first try as I soon found out this is a bad spot as the rear hatch hits them. Also not to sure there current location is effective as its after the break for the rear hatch and I may move them forward. Also may up the size to 1"Hx2"L. but this is what I had lying around.
noticeable changes? Not really but the rear end did seem more stable when cornering at speed.

Damn drive a yaris in md and have a long commute to fabricate...we must be brothers.

[Overkill Fab]

Originally Posted by malibuguy

Damn drive a yaris in md and have a long commute to fabricate...we must be brothers.

yeah it sucks! I think I've bought tubing off you for my Eclipse! LOL

[Yaristeve]

After being batted around like a ball of yarn in a kitty's paws today due to the wind, I was reminded of this thread and wondered if anyone had any updates...

[Klink10]

This interests me also.

[Idahotom]

Mine are still doing their thing, no mileage increase, discernible anyway, but much improved straight line tracking. A very strong direct x wind can still move it around a bit, but even that situation is improved.

[Yaristeve]

Originally Posted by Idahotom

Mine are still doing their thing, no mileage increase, discernible anyway, but much improved straight line tracking. A very strong direct x wind can still move it around a bit, but even that situation is improved.

Are your VGs the smaller 1" X 0.4" ones or the 1.5" X 0.?" ones? I noticed that ebay started a aircraft section in their ebay motors and there is an auction for the smaller size VGs.

[Idahotom]

Mine are the smaller ones. Bigger ones are not more effective I'm told, as the layer of air you are trying to control is .1 of an inch. Bigger may look more effective but there is a reason they make the small ones the size they do.

Having said that, I know the aircraft supply company I got mine from for my plane (MicroAerodynamics) DOES supply larger ones for use on the horizontal stabilizer, in front of the elevator. They make the elevator more effective at slower air speeds, like right when you really need it, landing. I only had enough of the small size left over from the plane install, so that's what I used on the Yaris. They make such a difference in the straight line stability, work so well in other words, I'm glad I didn't use the big ones.

[Yaristeve]

Thanks. I guess I will try them out...

[Rodger Wilco]

Yeah i dont think that you will get much more MPGs out of the VGs but I bet that it keeps dust off the back window more. I cant imagine that adding drag to the surface will increase your efficiency. On aircraft they delay airflow separation (as you know I am sure), but they also add drag.

Help me understand what benefit you would be getting out of them on the yaris, other than looks?

[Idahotom]

Increased stability at highway speeds (60 mph +) was my result, as noted. A dramatic difference, especially I had them taped on first while testing, drove for a week, then took them off and drove another week. All these miles on my usual well known route, that features several flags along the way to keep me informed as to any wind. This increased stability is especially noticeable when along a semi.

I didn't do it for looks, that's for sure. My mileage has stayed the same, no better no worse, and I keep real good track every fillup. My guess is the very slight extra drag is offset by the apparently cleaned up airflow on the ass end. Getting back to the looks thing, not my reason but now that I feel what they did for my car anyway, yes it does give people behind you at a stoplight something to cogitate over!

[WeeYari]

Your original pics are dead. How about some new ones since this thread is seeing a resurrection.

[Idahotom]

Crap, those pictures are history I guess. I'll take some new ones and post them in a day or so.....

[Idahotom]

new pictures.....

[dragoonmc]

Those are tiny little things

[Idahotom]

As big as they need to be, no bigger. And, the pair spacing may seem far apart, but that has also been deemed adequate by extensive testing. The boundary layer they influence is measured in a fraction of an inch, 1/16" or so, that word is from the airplane people who came up with the these in the first place. Those great big ones real close together are something dreamed up by car people, not airplane people. They may LOOK more effective but may not be.

[Yaristeve]

Doesn't the base of the antenna mess up the airflow to the middle pair? It would seem you would want two pairs of VGs at either side of the wake from the antenna base? Or, am I "off-base"? :D