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Old 12-09-2008, 10:23 PM   #6 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 55.44 mpg (US)

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

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 67.41 mpg (US)
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FYI, I have read that running a motor under heavy load with the brushes retarded can damage the comm. See: Obviously that'll depend on the degree... When I was playing with brush timing, I mistakenly set them retarded and could hear the arcing on the comm before I even got out of the driveway. It did scorch the edges of the comm bars.

I predict you're going to notice a difference in performance (speed) with the brushes advanced.

The motor in the ForkenSwift was spinning the "wrong" way in its previous life as a hydraulic pump motor. After we reversed the field connections internally to reverse its rotation, the brush timing of course changed from 17 degrees advanced to 17 degrees retarded.

Result (no load): 1480 RPM @ 12 volts retarded, vs. 2275 RPM @ 12 volts advanced.
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

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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