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Old 05-29-2009, 05:08 PM   #3 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,119

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 53.56 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 61.98 mpg (US)

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

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 64.03 mpg (US)
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Originally Posted by DieselHybrid View Post
1. Installed Vortekz vortex generators to reduce pressure drag. As per tuft testing, these have cleaned-up the flow a bit.
Of course, tufts streaming aft as a result of VG's doesn't necessarily equate to reduced drag. The VGs induce drag themselves in order to affect the flow.

Surprisingly, many of the underbody panels are dimpled (think oversized golfball)- which encourages early transition to a turbulent boundary layer.
The boundary layer by that point is more than likely already turbulent. The dimples are probably there for structural rigidity in a flat panel that may otherwise have a tendency to oil can. (Besides, there's no need to encourage a turbulent boundary layer unless you're trying to delay separation on a curve.)

Sorry for jumping on these points! Pet peeves of mine.

And congrats on an efficient new ride!
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: Oops, I did it again! Bought another cheap, 3-cylinder Mirage. Mods in progress...
Ecodriving test: Manual vs. automatic transmission MPG showdown

has launched a forum for the efficient new Mitsubishi Mirage - fuel efficiency info for Geo Metro owners - electric car conversion on a beer budget
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