[aerohead]

Originally Posted by 4drviper

I appreciate criticism but only when provided with a reasonable thought process. If one can say it won't work I can also say it will and it is not contributing to anything other than a blobby mess of opinions. All I got is "It ain't gonna work" without any hows. (That's how online forums get multiple threads claiming they get better mpg with hotter coolant but that's another story)

Let me give you an example. I think these will work in similar ways that roof extension spoilers work to reduce lift and drag in hatchback vehicles. Crosswind is never constant, which also promotes more abrupt separation on the trailing edge (in this case, A pillar and front roofline). The VGs when activated by crosswind, "...will prevent abrupt air separation at the trailing edges and therefore, contributes to lesser Wake creation, which in turn reduces the drag of the vehicle", quoted from explanation of hatchback rear spoiler.

This is why I also had an idea to just attach something to promote cleaner separation on A pillar but it already creates giant vortex as is which is out of my thinking capacity at this moment. End example.


I like to look at Toyota stuff since they seem to be going crazy with VGs for the past decade, which is my go-to item for when I can't modify the actual shape. The idea of letting the wind vary VG angle is probably not my original. If you look at any 15+ Toyota/Lexus vehicle from behind you can see the plastic cover under the trunk floor has four 1" x 6"(approx.) 2.5cm x 15cm plastic protrusions that are in line with the length of the vehicle. And I'm not going to bother posting visualizations of airflow under the car in varying crosswind because you should know it before you reply in this thread.

Toyota got the variable angle part down, and yes I'm still not certain if it wll help reduce the pull caused by crosswind and how to measure it if I could at all. Especially having seen that Airtabs do not "fill the wake" or "increase pressure on the trailing side", if I had a Camry or RX400 I'd already be testing the car with the strakes covered vs uncovered on windy interstate.


If those little pieces in line with airflow "creates more drag", I strongly believe it is smaller than margin of error in real world testing which is the only thing I could do so I won't be able to see it. But I will keep an eye out just in case I made wrong assumptions.
And, sure, airliners only have 2 of them but if they affected FE in any significant way, they wouldn't be on LH commercial airliners.

In crosswind, I actually do not know if they will help fight crosswind or not for the Airtabs did not reduce drag anywhere on my car. But like I explained in the OP I'm crossing fingers they would be efficient considering they're designed for vehicles much more sensitive to aero drag than cars.


And no those are 3/8". If one would care to read several posts above, we have been just talking about how 1" airtabs hurt MPG even on the trailing edge. It can be visualized how thin the laminar flow is on the front part of the car, put tufts on a straw perpendicular to the surface and give it some diagonal supports and go fir a drive.

What you're observing could be explained simply as a styling gimmick.
A perfect belly pan would be required for the diffuser to work in the first place. Failing that, it wouldn't matter what the diffuser looked like, it would be submerged in turbulence either way.