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Old 11-28-2007, 10:01 AM   #9 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,313

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

MPGiata - '90 Mazda Miata
90 day: 52.8 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 73.57 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 58.72 mpg (US)
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Undertook a little project this afternoon: replaced my stock non-folding but otherwise aerodynamically shaped driver's side mirror with a folding but otherwise not very aerodynamic mirror from the red Forkenswift car.

Above image: before - the stock mirror. (click to zoom)

Above: after - the folding mirror. It took a little cutting and drilling to make it fit, and I had to cut a piece of black plastic (left over krazy karpet) to fill the gap since the mirror base is a different shape than the OEM mirror). But all the modifications are hidden & reversible. Should I want to revert to original condition, I'll be able to no problem.

Above: it became clear pretty quickly that the folded mirror might present less area to the wind, but the open hinge was an aerodynamic disaster. So I drilled a hole on the hinge to hold a shaped gap filler made from a piece of sheetmetal contoured with bondo. A "pin" (bolt) fits in the new hole on the hinge. I can easily install/remove this from the mirror while sitting in the car.

The plan is to fold the mirror for highway use. I'm going to stick half of one of those round convex mirrors to the trailing edge of the folded mirror, so I'll still have some functionality.

Is it better than the stock mirror? Only if I fold it - it's clearly less aerodynamic than the stock mirror was.

Am I crazy? The evidence is mounting, isn't it.

Also, I have no way to definitively say that folded, this mirror will create less drag than the stock mirror. There's no question frontal area is reduced. But it will create its own unique turbulence, and I won't pretend to know that it will automatically be less drag inducing than the stock turbulence. I'm just guessing that it's going to be better.
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L

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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