LNF - Calibrating MAF frequency

[DrLoch]

Lol I HATED physics. I was seeing it as you are getting more airflow for the same velocity. 1000 Hz through a 3" tube vs a 4" tube - which has the greater mass flow?

"air velocity through the intake would be reduced for the same amount of airflow. " That being said, the mass of air flow is the same, the velocity of the mass air flow through the pipe is lower. I tend to agree with terminator2 it would be artificially low. The best way to answer the question is check it on an airflow bench.

[cobaltssoverbooster]

when going to a larger pipe the airflow is higher thus you must lower the numbers so the airflow rides higher up on the scale also demanding more fuel.

[Baldturbofreak.com]

More molecules touching the element, less resistance.
If you have a larger pipe, there is more passing thru the sensor for a given freqency, requiring you to increase the values of mass for a given frequency.
Then you obtain the required AFR.

[cobaltssoverbooster]

really am i wrong then cause i had to lower my values to make it correct.

[EaglePerformance]

More molecules touching the element, less resistance.
If you have a larger pipe, there is more passing thru the sensor for a given freqency, requiring you to increase the values of mass for a given frequency.
Then you obtain the required AFR.

With a larger pipe, keeping the mass air flow the same, (of course we want MORE flow, that's why the bigger pipe), the element will "see" less molecules because 'assuming' the same mass is moving in a bigger area, velocity will be less, causing less to be "seen" in any one area, (the element), so the element "sees" less even though the same mass is actually there.

[cobaltssoverbooster]

8D yay im right

[Terminator2]

Larger diameter tube will read lower than actual because the sensor will see less airmass than actual. One needs to increase the value for mass airflow for a given frequency to acheive the proper A/F ratio.

[acesneights]

Whats the size of the stock intake? Isnt it already close to 3"? It looks like it anyways.

[cobaltssoverbooster]

it is but its still usually not calibrated perfectly from the dealer anyways unless your lucky. mine was off

[Terminator2]

it is but its still usually not calibrated perfectly from the dealer anyways unless your lucky. mine was off

Mine is off 4-5% from the factory too.

[acesneights]

Well mine was reading -1.6%, so I multiplied the maf vs. frequency table by .94. And now my ltft is 0 throughout my entire pull. I take thats good right? This was my first time tuning my car.

[cobaltssoverbooster]

right on but pulls are more stft so you want the ltft to be zero saves lots of gas and makes it run beautiful. the stft zero im sure is all maf of course and full pull would be reading of lbs.min and g/sec to adjust fuel. is that right? i men my truck does that, uses stft only at wide open

[acesneights]

My stft is between 8 and -8. How do I make that more close to 0?

[cobaltssoverbooster]

if its straddling both sides of the zero equally all over you will prolly not get any closer than that.

[Terminator2]

My stft is between 8 and -8. How do I make that more close to 0?

You need to make a histogram of load and rpm vs STFT. Then use the data to adjust your MAF correction table.

[justmike]

You need to make a histogram of load and rpm vs STFT. Then use the data to adjust your MAF correction table.

Or he could just use this one http://www.hptuners.com/forum/attach...5&d=1224373380