The Airtabs have a definate direction to face and create a clockwise vortex and counter clockwise vortex and should be placed 4 inches apart. The idea is to prevent reverse air flow back against the rear of the vehicle which represents drag and turbulance. I wish the improvement was greater to justify the cost but I guess at some point I will get a few and try them.
According to the airtabs website (in "How do they work"), they create vortices.
Yes. Metro, I've been running my airtabs for sometime now, and when I drive through the rain, and a vehicle is behind me with thier lights on...I can significantly see the votices. Also, whenever I cruise down a dirt road above 40mph I can see them.
"You have to know the truth, and seek the truth, and the truth will set you free."
All I can say is that they are symetrical, but the air hitting between the vanes is bumped up...might create a spin? Maybe there is an interaction between this higher pressure and the lower pressure air between the airtabs?
the typical vg obviously creates a spin.....
Leading the perpetually ignorant and uninformed into the light of scientific knowledge. Did I really say that?
a new policy....I intend to ignore the nescient...a waste of time and energy.