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MAF calibration adjustments from LTFT histogram

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Old Nov 2, 2005 | 06:08 PM
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Default MAF calibration adjustments from LTFT histogram

Man Ive had a hard day at work and having major brain delays in calculations.

If Im looking at the MAF Table and LTFT+STFT histogram, if I see say a 5% value in 5000hz, do I want to go to the Calibration table for the MAF and add 5% to the value of say 32g/sec? Like do I multiply 32 by 1.05 ? Or should I be subtracting it? Like 32 x .95 ? Damn my brain is fried, system malfunction going on.

Dixit
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Old Nov 2, 2005 | 08:45 PM
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I calibrated it that way and its worked well for me. Below is a link to a write up I did tuning the maf table according to trims
http://www.performancetrucks.net/for...d.php?t=346549
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Old Nov 2, 2005 | 08:53 PM
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After thinking about it you were right as I suspected after a few hours. So if my value shows up as +5% I want to add 1.05 to the value to get it almost to 0. Or I can add 1.07 to get it to -2.

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Old Nov 2, 2005 | 08:56 PM
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Yes, if positive ltfts multiply the value at the given hertz column by 1.xx, with xx being the ltft value. I just eyball the ltfts while watching a playback of a log run, works well for me.
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Old Nov 2, 2005 | 09:15 PM
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using the 2.0 histograms that I built
www.audiohelix.com/file

Logging LTFT+STFT and MAF HZ
you can do a Copy/Paste Special/Multiply by %
as you get it real close you can start to do a Multiply by %-half so you dont overshoot...
when its where you want...just add another 1% or 2% to the table to make it richer
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Old Nov 2, 2005 | 09:17 PM
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Yea thats the histogram I was talking about. Just wanted to know which way to do the multiplication. But now I know. Thanks.
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Old Nov 3, 2005 | 07:28 AM
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In HPT, do you read an average of the cell values or can you switch between peak, average and low values in the LTFT histogram? If so, what values do you use to update your VE table.

I know in Live, we can display high, low, average and cell count in the histogram . I usually adjust my VE table using the average value.
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Old Nov 3, 2005 | 07:56 AM
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Originally Posted by jub jub
In HPT, do you read an average of the cell values or can you switch between peak, average and low values in the LTFT histogram? If so, what values do you use to update your VE table.

I know in Live, we can display high, low, average and cell count in the histogram . I usually adjust my VE table using the average value.
All correct... you can do all these with HPTuner. Everyone I talk to uses the average values....
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