air dam and vortec generators

[SL8Brick]

Originally Posted by AMX

Are the "Vortekz" fins worth buying?

I suppose that's a matter of opinion. Since VGs can be easily made at home from common materials, some folks find it difficult to justify the $20 cost. On the other hand, they could be considered more aesthetically pleasing than many homemade VGs...they can be easily painted-to-match for an OE appearance...and IMO, they're really a decent quality product for the $$ (although I do find some of their marketing techniques a bit questionable).

[AMX]

I don't mind paying the $20 for them. The Vertekz ones look good and if it's going to help slightly in gas mileage, i'm all for it. Have you had any experience with painting them? I'll probably get the primed ones if I do order.

[SL8Brick]

Originally Posted by AMX

Have you had any experience with painting them? I'll probably get the primed ones if I do order.

You can paint them with any enamel spray paint. But I had 2 sets professionally painted by a local bodyshop for my nephew's Camaro and my Dad's Mazda5. The plastic is somewhat pliable, so I had the bodyshop add a flex agent to the paint so it wouldn't crack over time.

[sonyhome]

OK, all that is cool, but what's the MPG gains from those lil' guys?
0% or 15%???

For some reason I never see that answer. I'd be happy
to buy and paint some if they make a difference besides
subjective "stability" improvments.

Also what's better? VGs or a spoiler above the trunk door
(I drive a CR-V, and even with its square shape doesn't
come with a stock spoiler unlike other SUVs/Vans).

Not sure anyone has made an objective measure of those
on cars with a systematic approach, and gotten positive
MPG results. At least I haven't seen these posts.

Cheers!

[SL8Brick]

Originally Posted by sonyhome

OK, all that is cool, but what's the MPG gains from those lil' guys?
0% or 15%???

For some reason I never see that answer. I'd be happy
to buy and paint some if they make a difference besides
subjective "stability" improvments.

Also what's better? VGs or a spoiler above the trunk door
(I drive a CR-V, and even with its square shape doesn't
come with a stock spoiler unlike other SUVs/Vans).

Not sure anyone has made an objective measure of those
on cars with a systematic approach, and gotten positive
MPG results. At least I haven't seen these posts.

Cheers!

IMO, its unrealistic to expect a drastic change in FE from any type of VG by itself. They're probably best used as a part of an aerodynamic supplement package(ie:w/grill block, underbody trays, ect.) Then again, I suppose its going to depend on the bodystyle and finding the optimum mounting position. Mitsubishi's testing concentrated on threebox sedans, so I believe that's where you'd potentially see the best improvement. I've installed them on three different twobox vehicles...my `93 Volvo wagon, a `99 Audi A6 Avant, and a `06 Mazda5. Like I mentioned in another post, none of these vehicles have yielded an increase in overall FE from the VG's alone. But I do know they're creating vortices. While driving on rainsoaked roads @ highway speeds, 2 counter-rotating vortices are faintly visible in the water mist behind the car. My Dad also noticed this in his Mazda5. And my friend with the Audi wagon says his rear window stays cleaner on the highway.

And Cheers to U2!

[sonyhome]

OK...

Did you also put VG's on the side of the 2-box cars you have? The airtab car application (Gen'1 CR-V!) claims 10% saving but has 7 airtabs on each sides. Most other applications claim gains on guzzlers like 8MPG pickups or rigs... Not relevant.
http://www.airtab.com/Images/photoga...allery1.htm#AP

Why no visible gains?

Can we can assume the VGs create a longer tail at least on the top part of the car. The air will not wrap down the rear windshield down towards the undercarriage to increase turbulence.

To get a clean teardrop, maybe the air flow also has to be somewhat cleaned on the undercarriage and sides too.

The VGs should help getting a stable depression behind the car. It would help get the turbulent pressurized undercarriage air out, and generate less drag from trapped pressured air.

[SL8Brick]

Originally Posted by sonyhome

Did you also put VG's on the side of the 2-box cars you have?

No, I did not. I installed the delta fins on the roof as recommended by the mfgr which concurs with the Mitsu PDF. "Vortekz" claims that the fins can be mounted on the sides, but stops short of saying exactly how/where to mount them. I've considered mounting Airtabs on the sides, but a secure mounting area for the larger tabs is limited on my Volvo.

Originally Posted by sonyhome

Why no visible gains?

Possibly because all three vehicles lack prime driving/testing conditions. Most of my daily commute is spent below 40mph. My Dad's commute is pretty much the same. Both of us have experienced moderate gains on long highway trips, but I find it difficult to attribute it to the VGs alone. And my friend with the Audi wagon is notorious for his lead foot and keeping his rear window clean was the only reason he wanted them in the first place.


And finally, green swift....where are those pics???

[sonyhome]

I contacted a vendor of VGs, and the saying is gains should be around 10%, but can't guarantee because of test conditions.

Air Flow system:
http://www.prfprod.com

Mileage is tough to determine for a single vehicle. So much depends on the driver, conditions, vehicle, etc...
In general we have seen on the average of 8 to 12 percent increase in fuel mileage, on passenger cars and trucks. You may see mileage increase up to approx 26 or 27 from 24mpg. Unfortunately I would be reluctant to guarantee anything.
On my motorhome I have seen about a 20% increase in fuel mileage at 60MPH, and still see about 12% at 75MPH. Typically I would see a reduction in fuel mileage at 75MPH of about 20%. Again, every driver is different. I typically do some drafting with trucks and larger vehicles when on the open road. The biggest improvement was the handling in a crosswind or turbulence coming off another vehicle. It just goes straight down the road.
...
The Vortex Generators that we manufacture are much easier to install than the ones you mentioned because they are on a single panel. We recommend them across the rear top most trailing edge of the vehicle. The most effective installations are if they are placed on the sides and bottom of the vehicle as well. I always recommend using the biggest ones that you
have sufficient mounting area. I have attached a pic of our 2, 3, and 4 inch Vortex Generator Strips that are 12 inches in length.
...
Mike Nish

[sonyhome]

Aren't you talking to do what bug deflectors do with VGs? i thought the bug deflectors were detrimental to aerodynamics.

[Hateful]

I threw together a couple for testing; the shark fin and the rat. They might be too big for the roof.

I was thinking make one more and do a string on the back window test with none on one side and the VGs on the other.