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Old 12-04-2009, 09:22 PM   #2 (permalink)
cfg83
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Join Date: Dec 2007
Location: Southern California
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1999 Saturn SW2 - '99 Saturn SW2 Wagon
Team Saturn
90 day: 40.49 mpg (US)
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gardenman -

Very cool idea. I went here for a comparison :

Fatboy Raceworks Graphical Transmission Gear Ratio Calculator

And came up with this :



Transmission One represents my MP2 5th gear swap. Transmission Two is identical except for the custom 0.510 5th gear.

I picked 1000 RPM as the "redline" because I wanted to know the minimum MPH needed to stay above the "lug line" of the engine. 1000 is roughly close to the idle RPM of the S-Series. Anything below 1000 RPM makes it hard to drive the car. This would actually force me to drive faster on average.

I plugged in other RPMs to figure out other MPH in 5th :

Code:
RPM    0.605       0.510
        MPH         MPH
1000   29.63       35.15
1200   35.55       42.18
1400   41.48       49.20
1600   47.40       56.23
1800   53.33       63.23
2000   59.25       70.29
It looks like ~1800 RPM would be your freeway RPM.

I am not in super hilly country, but if I were in pure flatlands, I might go for it.

CarloSW2
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