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      03-29-2011, 12:54 PM   #185
spdu4ea
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Quote:
Originally Posted by swamp2 View Post
Is the "problem" the uniformity of the gains across the entire rpm range, the peak gained value or the average value gained?
Whichever raises your red flag most I suppose. For me the uniformity of the gains across the rpm range caught my eye as something unusual enough to quantify.

Quote:
If the variable being condensed to a single value for the distribution plots is simply the average % power gained that is a totally separate issue from the gain vs rpm curves linearities.
Perhaps you could use average power gained, but what I looked at was the acceptable range of deviation in percent power gained across the rpm range.

Quote:
Also, somewhat nit picky, but the values in the y axis should be 100 times larger if the title of the chart is "Percentage...".
Haha, good catch and absolutely true. I formatted those spreadsheet cells to display in percentage but apparently visual/display formating does not transfer to graphs.


Quote:
In my view the linearity is the clue to a cheat and then the average value of the curve also becomes suspect. Would a very linear curve of gain vs. rpm but at a constant (low) say 4% gain be a red flag? I don't think it would be. It is the combination of high linearity and high average gain that is the "double whammy".
I think it is and those normal distribution graphs are representative of this. OE's gain at Gintani's is only ~4.6% over stock which by itself doesn't raise any flags.

The remarkable linearity (as you aptly put it) of the raw gains are:

OE @ Gintani:
4000 9
4500 10
5000 11
5500 12
6000 13
6500 14
7000 15
7500 16
8000 16


ESS:
4000 6
4500 6
5000 7.5
5500 13
6000 12
6500 16
7000 17
7500 15.5
8000 17.5


AA:
4000 13
4500 13
5000 14
5500 20
6000 27
6500 31
7000 23
7500 26
8000 29


GIAC:
4000 7
4500 9
5000 13
5500 11
6000 17
6500 16
7000 21
7500 21
8000 25



Quote:
Really you might want to make 2 sets of plots. 1 that is simply average % gained across all rpms vs. vendor. The other would be some measure of the linearity of each curve. The most simple metric would max-min. You could also use the "RMS" value (square root of the sum of the squared deviations of each rpm point - (Sum((value-mean value)^2))^1/2 ).
What I've done is very similar to RMS, but you're right it would be interesting to see the average % gained at each rpm point. I'll try and work on it tonight...
Appreciate 0