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      06-03-2013, 02:16 PM   #31
swamp2
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Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

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Quote:
Originally Posted by CanAutM3 View Post
Just for the sake of it, could you run a simulation with the following gear ratios:

FD: 3.15
1: 4.25
2: 2.57
3: 2.03
4: 1.60
5: 1.27
6: 1.00
7: 0.75

I am curious to see the acceleration curve it would generate. I am guessing a very smooth curve (except for the 1-2 shift) with progressively decreasing acceleration as the speed increases. Again here, just wishful thinking on my part .
Generally results across gears are relatively insensitive to such changes, whereas some individual results will show sensitivity. Again it all comes down to power, peak performance depends on peak power, which means torque + gearing. If you just focus on power, gearing basically drops from the equation (given it is not something entirely unreasonable for the car).

Here are the actual acceleration profiles. Almost identical except in 1st gear.



Here is the summary of numbers. No practical change in 1/4 mi time nor trap. Surprised? I'm not. This is very much like the final drive mod debate! Did you follow one or more of those?...

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