MAF transfer curves

[Will McGonegal]

We have used Ford MAF sensors at our lab for various projects.  We calibrated
them against a Laminar Flow Element (that we paid lot's of money for, and
believe to be very accurate).  The voltage vs. flow output is not linear on the
Ford units we use.  Here is the curve fit for one of the units we calibrated:

Flow (scfm) = 0.6066 - 1.475v + 20.05v^2 - 5.9233v^3 + 1.3292v^4

We calibrate each MAF unit we use.  They have similar curves, but there is some
variability.

I have also heard that the GM units give a frequency output, not voltage.  I
don't recall if it is linear with flow.

Will McGonegal
Electrical Engineer/Dynamometer Developer
Emissions Research and Measurement Division
Environment Canada
Ottawa, Ontario

> ------------------------------
> 
> Date: Wed, 3 Jan 2001 08:00:58 -0500
> From: Rodney_L_Wiggins at keybank.com
> Subject: MAF transfer curves
> 
> Different transfer curves for MAFs?
> Is this true?? I was led to believe that voltage output was linear
> with respect to airflow for all makes. 
> > ------------------------------
> 
> Date: Wed, 3 Jan 2001 10:09:34 -0500
> From: "Shirley, Mark R" <MarkRShirley at eaton.com>
> Subject: RE: MAF transfer curves
> 
> At least on the Ford MAF's I had transfer functions for,
> they were all linear voltage 0-5V with a little rolloff on
> both ends.  These were Hitachi parts.
----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org