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Old 09-11-2009, 09:40 PM   #39 (permalink)
MetroMPG
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,526

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

MPGiata - '90 Mazda Miata
90 day: 52.71 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: 60.06 mpg (US)
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Quote:
Originally Posted by Christ View Post
Not that I'd recommend it, but you could actually mill short-term use gears by hand (with a lathe and files).
The difficult part though are the gear hubs. Splined on the output shaft cog, and freewheeling on the input side, with the synchro & sliding collar that have to fit the shifter fork. I suspect the actual making of the teeth for a "proof of concept" gear set is the easy part! Getting them on the shafts and making them "shift-able" is the challenge.

The other thing to consider in that arrangement is that if the test set of gears start to wear and shed filings into the oil, it'll accelerate wear through the rest of the transaxle.

Zero: sure, wouldn't hurt to ask. I've seen prices everywhere from $2k to $500-800.

Robert: the gears aren't simply swappable. EG: the small cog of the current 2nd gear set is actually integral to the input shaft. I would have sacrificed the input shaft to do the surgery to put the 5th gear hubs into the 2nd gears.
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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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