RomRaider

I really like the additional sheets youve added.

It looks like you are manipulating the ouput correctly, adjusting higher voltage cells by altering the cal line in lower voltage cells. Have you observed more accurate fueling from this revision?

Good to hear! Yes, even with the first smoothed MAF curve, fueling and low-end driveability improved significantly.
I think a lot of it has to do with what you said in your first post and what I think we've all seen (at some point)
where the ECU 'likes' a smooth MAF curve. Must have something to do with the interpolation it itself does between the points
and how the ECU logic goes iterates through the MAF curve data points as you trace up and down the curve while driving.

I've noticed smoother, improved low speed acceleration and deceleration (seem the TCU indirectly also likes a smoother
MAF curve which must translate to better Load transitions, Requested Torque, etc.), tighter CL fuel trims
and a lower OL AF Error%.

Hi all , I have corrected maf using vgi tool and also rescaled as the BRZ maf useable V is only around 4.1-4.2 in NA form

I have smoothed using the maf shaping utility , just wondering if someone could look over it and see if I have don't it right

thanx heaps for help

It Looks like youve got the right idea, the caclulated curve looks to fit the scaled MAF well. Ultimately it all comes down to performance. Is your fueling more accurate after smoothing?

6/25 added another version with a sheet that can be set up to show AFR delivered by an incorrect scale.

I must be an idiot because I'm so confused, I want to smooth my maf but i'm lost. can anyone dumb it down even further?

0.94 0.98 1.02 1.05 1.09 1.13 1.17 1.21 1.25 1.29 1.33 1.37 1.41 1.48 1.56 1.64 1.72 1.80 1.88 1.95 2.03 2.11 2.19 2.27 2.34 2.42 2.54 2.66 2.77 2.89 3.01 3.13 3.24 3.36 3.48 3.59 3.71 3.83 3.95 4.06 4.18 4.30 4.41 4.49 4.57 4.61 4.65 4.69


1.36 1.79 2.02 2.27 2.52 2.90 2.97 3.16 3.16 3.52 3.80 4.23 4.77 6.07 7.27 8.27 9.75 11.92 13.73 15.41 17.61 19.68 22.40 25.43 28.24 32.11 37.80 43.63 48.74 54.77 61.78 69.66 78.04 88.20 100.21 113.65 127.78 142.38 156.30 168.11 183.00 212.00 260.70 280.86 301.03 311.14 315.24 319.36

If you use ECU flash and look at your MAF area with the graph view you can see how smooth your curve is. Anything that is spiky or uneven could use some work.

Also smoothing out your MAF will take some data logging of your STFT and seeing where you are running rich or lean.

LTV if you can use it will also show you were your MAF is off.

i have my maf pretty well dialed in. working on the closed loop my biggest ltv is like 4-5%, as for open loop i have afr almost dead on but the curve is bugging me though and i need to smooth it or i wont be satisfied lol

plot both the stock MAF scale and your modified one (2 times) start modifying one of them to be smooth perfectly like the Stock MAF Scale and be as close as possible to the modified one that gives you the best AFR.

hope it's clear!

So I have been playing with my o2 sensor trying to smooth my idle. I remembered this thread and decided to plot my o2 sensor map along with the a couple derivatives just for giggles.

I found a jumping 2nd Derivative. You are right about how hard it is just to input numbers and see what you get. I was able to smooth it out a little and noticed improvement.

So I am having trouble understanding how you built the spreadsheet. Do you have any hand calcs that might give be a better idea of what you did? Now on the o2 sensor map, the current crosses 0. I am not sure what that will do to the equation you developed for the MAF.

Any help would be appreciated.