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MetroMPG · 11-28-2007, 04:12 PM

Where ERPWR = "engine revs per wheel rev" (gear ratio * final drive ratio)

gear ... gear ratio ... ERPWR, stock tranny ... ERPWR, 3.52 final (4 cyl) tranny

1 ... 3.416 ... 14.99624 ... 12.02432
2 ... 1.894 ... 8.31466 ... 6.66688
3 ... 1.28 ... 5.6192 ... 4.5056
4 ... 0.914 ... 4.01246 ... 3.21728
5 ... 0.757 ... 3.32323 ... 2.66464

So I'm kind of "gaining" another gear. The stock tranny 5th gear/diff product is actually slightly shorter than the product of the 4-cyl tranny's 4th gear/diff.

11-28-2007, 04:12 PM	#10 (permalink)
MetroMPG Batman Junior Join Date: Nov 2007 Location: 1000 Islands, Ontario, Canada Posts: 22,534 Blackfly - '98 Geo Metro Team Metro Last 3: 70.09 mpg (US) MPGiata - '90 Mazda Miata 90 day: 54.46 mpg (US) Appliance car Mirage - '14 Mitsubishi Mirage ES (base) 90 day: 57.73 mpg (US) Thanks: 4,082 Thanked 6,979 Times in 3,614 Posts	Where ERPWR = "engine revs per wheel rev" (gear ratio * final drive ratio) gear ... gear ratio ... ERPWR, stock tranny ... ERPWR, 3.52 final (4 cyl) tranny 1 ... 3.416 ... 14.99624 ... 12.02432 2 ... 1.894 ... 8.31466 ... 6.66688 3 ... 1.28 ... 5.6192 ... 4.5056 4 ... 0.914 ... 4.01246 ... 3.21728 5 ... 0.757 ... 3.32323 ... 2.66464 So I'm kind of "gaining" another gear. The stock tranny 5th gear/diff product is actually slightly shorter than the product of the 4-cyl tranny's 4th gear/diff. __________________ 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