Air Tabs - air vortex generators to reduce vehicle drag

[AZRedhawk44]

http://www.airtab.com/

Anyone have 'em?

Anyone use 'em?

Anyone know if they're a load of bunk or supposed to really help?


Ever since I installed my camper shell on my pickup, I've lost about 1-1.5 mpg on my truck.  I'm thinking about installing these around the perimeter of the camper shell on top and sides, to see if I can regain that fuel efficiency (and perhaps more).  They're $2.75 a piece and are supposed to be spaced 3 per foot.  I have a 4 foot wide roof and 2 feet each on the sides for a total of 8 feet, or 24 total units.

Reading online reports, it seems they are oversized for tiny little eco-weenie cars and create more drag than they produce in benefit.  But they help truckers immensely.

My Dodge Ram 1500 with big negative-pressure-creating camper shell and sheer boxy rear end would be fighting a stronger negative pressure differential than a little Honda Insight.  I'm thinking my truck might be big enough to derive more benefit from them, than cost in drag.

It would cost $66 to outfit the outer edge of my camper shell along the top and sides.  Or, $33 to just do the top edge of the camper shell.

[RoadKingLarry]

My initial response would be
I smell bullshit.

[zahc]

My dad bought those back when he was still trucking over the road. He put them on the back of the cab of his semi truck, but he didn't put them on the back of his trailer because he pulled the company's trailer. He bought the clear ones. If I remember, he didn't notice any mileage increase or decrease. Based on our typical data, we would easily have noticed a 1/2mpg increase, but if the increase was more like .2 mpg it's hard to say if we would be able to tell. The airtabs stick very well and I don't think any of them fell off, but the clear ones get ugly because road grime gets under them. 

[roo_ster]

Do they sell the fuel line magnets, too?

[mtnbkr]

No, but they sell electric turbochargers.

Chris

[MechAg94]

I'm with the rest of them, I can't see it making much difference.  If it made a huge difference, I would think the manufacturers would add them and lobby the Govt to change the way MPG is measured.

[wmenorr67]

My dad bought those back when he was still trucking over the road. He put them on the back of the cab of his semi truck, but he didn't put them on the back of his trailer because he pulled the company's trailer. He bought the clear ones. If I remember, he didn't notice any mileage increase or decrease. Based on our typical data, we would easily have noticed a 1/2mpg increase, but if the increase was more like .2 mpg it's hard to say if we would be able to tell. The airtabs stick very well and I don't think any of them fell off, but the clear ones get ugly because road grime gets under them. 

This.  If they actually were worth the money the company would have them on the trailers.

[zahc]

This.  If they actually were worth the money the company would have them on the trailers.

An economics professor and two grad students walk into a bar.

The grad students notice that there's a $100 bill lying on the floor, but the professor walks right over it.

Students: "Aren't you going to pick up the $100 bill?"

Professor: "If there really were a $100 bill on the floor, someone would have picked it up already"

[Nick1911]

I'm going with fuel saver scam.

[AJ Dual]

No, but they sell electric turbochargers.

Chris

I saw this at my local mall's "As Seen on TV" store full of infomercial gadgets. http://www.fuelshark.org/

I just about pissed myself laughing. 

Although you can save LOTS of fuel on the Interstate. You just have to be willing to draft a semi truck at about 2-3 car-lengths for as long as you're able. 

[charby]

No, but they sell electric turbochargers.

Chris

and MAP sensor +mpg +hp gizmos.

[birdman]

Vortex generators only work to energize a boundary layer to maintain flow attachment longer, as such, they need to be placed where the layer would normally trip, or a bit before.  In other words, if it's in dirty air, they don't do anything, and likely make things worse.  They are best used to reduce drag when you have smooth flow, and then the surface moves away from the flow (e.g. Top of a wing, or at the end of a sedan's roof before the rear glass).  On a camper shell or trailer, those aren't really happening.

[Perd Hapley]

My motor-head, drag-racing friend was much less scientific than you lot. I showed him the picture of the tabs on the yellow 'Vette. He just said, "Yeah, that looks gay."

[bedlamite]

I searched a few auto forums. They can change aerodynamics, but every case is different. Some say mileage improved, some lost mileage, some there was no change.

http://autospeed.com/cms/A_3061/article.html