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Old 04-08-2021, 12:10 PM   #56 (permalink)
MetroMPG
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,527

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)
Thanks: 4,078
Thanked 6,976 Times in 3,612 Posts
AC "delete"

The Canadian market is one of the few places the BASE trim Mirage came without air conditioning. However my current Mirage is the higher trim with AC.

Simple AC delete mod:

Reduce belt friction & a bit of rotating mass by swapping the serpentine belt from the AC model (top engine) with the shorter one from the base model (bottom - green) thus bypassing the AC pulley:






Unfortunately, the part number for the non-AC serpentine belt is ridiculously difficult to find (a lot of Canadian parts stores use US databases, it seems, where the non-AC car does not exist).

Annnnnd worse than that... the part number a helpful soul gave me was slightly wrong, so the belt I got was slightly too short.

All of which I discovered AFTER struggling valiantly to install the most difficult belt I've ever swapped in my life!

Oh well, I eventually got it on.


Prognostication...

To scientifically estimate the potential gains, I spun the AC pulley by hand with the belt off.

Turns out it freewheels on the smoothest bearings in the known universe. You could go get a coffee and it'll still be spinning when you get back.

So I figure this mod is good for 1.3 TBSP per year in fuel savings and +0.000092 HP.

110% worth it!
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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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Ecky (04-08-2021), Joggernot (04-10-2021)