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Old 03-02-2010, 09:41 PM   #5 (permalink)
MetroMPG
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,534

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

MPGiata - '90 Mazda Miata
90 day: 54.46 mpg (US)

Appliance car Mirage - '14 Mitsubishi Mirage ES (base)
90 day: 57.73 mpg (US)
Thanks: 4,082
Thanked 6,979 Times in 3,614 Posts
Quote:
Originally Posted by jimepting View Post
BTW, have you driven an Insight?
He has one.... but no garage entry for it which would put his contributions in context (hint, hint!).

Quote:
Originally Posted by RobertSmalls View Post
If all you have is a long, steady grade, you might be able to tease a CdA number out of it,
If you simply want to know if a particular aero mod is better, worse or indifferent from baseline, I wouldn't worry about the math or finding the "perfect" road. Simply repeat the coastdown over the same stretch (absent other traffic, in consistent weather conditions, with a fully warmed up drivetrain) and note the delta in times. The higher the initial speed and the longer your coast, the better.

It's tasty knowing the actual MPG impact, but "powered" testing is more difficult.
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Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
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
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