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Old 06-21-2009, 11:49 AM   #10 (permalink)
MetroMPG
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Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

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90 day: 53.56 mpg (US)

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90 day: 61.98 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 58.72 mpg (US)

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Good experimenting, Deezler.

I wouldn't expect to see any MPG improvement show up - it'll probably be too small to see above the normal statistical noise of tank-to-tank variation. Recall that Mitsubishi estimated a drag reduction of just -0.006 in their study.

I like your idea of putting the VG's aft of the physical "peak" of max frontal area projection. And they still clearly influence airflow placed at the top of the window!

The $60,000 question is whether their additional induced drag (from their vortices) is greater/equal/less than the potential for drag reduction because of a smaller wake.

Quote:
Originally Posted by superchow
One thing I was wondering about was if the wind noise would be reduced if the airflow is smoother. Did you notice any difference?
In each case where I tested VG's, I felt there was more noise when they were in place. Subjective though. Take 2 grains of salt and call me in the morning.
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