View Single Post
Old 05-29-2009, 05:08 PM   #3 (permalink)
MetroMPG
Batman Junior
 
MetroMPG's Avatar
 
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)
Thanks: 3,754
Thanked 6,568 Times in 3,405 Posts
Quote:
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.

Quote:
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



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote