Modified MAF

[darkhorizon]

The stock MAF is from 1500 to 11500Hz with calibration every 125Hz. If you are not modifying the sensing capability, but are simulating a higher ceiling, then you're increasing g/sec spacing.

idle on most any stock maf is above 3200. I idle at about 2300 on a modded maf. Its not linear... but I gain all most anyone would need and lose only a fraction of resolution... Resolution I dont even need as most will not be spending much time between 6000-10000hrz anyway.

 

[darkhorizon]

What does the LQ4 or other GM mafs max at? I guess this should be answered in lb/min or g/s compared to the stock one.

lq4 is about 20 more g/s than stock... LT1 is about 45g/s more than stock. Modded is 200 more.

 

[matt5112]

Stock valvetrain, ported TB, 2300 Hz idle with stock MAF.

2900 Hz cold idle.

Stock MAF isn't linear either.

The PCM can be told any g/s value for any frequency from 1500 to 11 500 up to 512 g/s. Which is a lot of air to be pushing through a 3.8 L engine.

Whats the point of a modified MAF if you can run an AFC? Especially if the AFC is more predictable than the modified MAF.

You'll still hit the 512 g/s limit if you make enough power. Once there, without being able to adjust the cylinder displacement, unsure how you'd adjust fueling short of playing with the PE vs RPM. However we lack much resolution there so I'm not sure how you'd maintain a consistent AFR.

 

[darkhorizon]

Avoiding the 512 limit is the easy part.... you can just scale the maf table vs the injector flow