View Single Post
Old 07-03-2014, 03:03 PM   #6 (permalink)
Do more with less
Join Date: Jul 2010
Location: North Eastern Missouri
Posts: 927

OD - '05 Ford Econoline
90 day: 18.64 mpg (US)

Joetta - '86 Volkswagen Jetta Turbo Oil Burner
90 day: 49.71 mpg (US)

Benzilla - '85 Mercedes Benz 300D
90 day: 28.08 mpg (US)
Thanks: 65
Thanked 173 Times in 110 Posts
I did yarn testing of my VW. I put on some heavy wire masts on the back and tied a flag every 3". Once you see where the wind is not turbulent you can use that point for an "anti spoiler" What surprised me is how quickly air went from being fairly organized to a frenzy. It would only stay together a few inches past the edge of the body.

Here is an over the shoulder pic of it a few inches behind the back window.

I used a section of cattle fencing. to hold the tufts. I know a guy who uses a fiberglass wand (fishing pole) with a bit of yarn on it. He can hold it where he wants to test.
"A man is not finished when he is defeated. He is finished when he quits."
Richard M. Nixon

"The reward of suffering is experience."
Harry S. Truman

“There's no way to rule innocent men. The only power any government has is the power to crack down on criminals. Well, when there aren't enough criminals, one makes them. One declares so many things to be a crime that it becomes impossible for men to live without breaking laws.”
Ayn Rand
  Reply With Quote
The Following User Says Thank You to Varn For This Useful Post:
Joris (07-03-2014)