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Old 08-11-2011, 01:22 PM   #67 (permalink)
MetroMPG
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,532

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

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

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car Mirage - '14 Mitsubishi Mirage ES (base)
90 day: 62.14 mpg (US)
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Quote:
Originally Posted by Cd View Post
What would be the proper way to test a car too old to use a ScanGuage and no cruise control ?
By the way, I use a SuperMID .
The SuperMID has a "resettable average" fuel consumption function, I assume. You need that.

Without cruise control, you're likely to suffer from more variability in your runs (both speed & fuel consumption), especially if your test route isn't flat & devoid of other traffic (aero effects). You'll see just how much variability there is after you do your first set of "A" runs. If your fuel consumption figures are grouped very tightly / consistently in the set of runs, it may suggest you've got a steady foot.

Does the SuperMID also have a resettable average speed display? You could monitor how accurate your foot is, if it does.

If you're only testing aero mods, you could get around this problem by just doing coastdown testing. It's perhaps not as satisfying as seeing actual MPG figures, but you'd still get a relative indication of whether a mod has any impact vs. coastdown runs in the "control" state.
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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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