MAF to MAP

[the Fredericks]

I was thinking about that pitot tube thing but I'm afraid of the liability
issue in parking lots...those pitot heaters get hot, and what about the eye
poke hazard?

Yes, on 7148 ECMs (my application) the MAF input is still limited at a
point.  But, extended range patches are available...as "Deepthroat", the
shadowy GM powertrain engineer, recently clued me in, the MAF signal is read
using a free running counter started at each pulse; the resulting counts are
then multiplied by a range constant, to compensate for linearity and allow
the resolution to be scaled at higher flow.  The resulting "quasi 16 bit"
number is used in the MAF lookup tables.  If you change the top constant,
you can double the range of the top section of the MAF table.  That's
regurgitated info; I didn't figure it out myself, so don't ask me any
piercing questions, okay?  :-)

Kendall Frederick

-----Original Message-----
From: owner-gmecm at esl.eng.ohio-state.edu
[mailto:owner-gmecm at esl.eng.ohio-state.edu]On Behalf Of Dave Zug
Sent: Thursday, August 19, 1999 1:22 PM
To: gmecm at efi332.eng.ohio-state.edu
Subject: Re: MAF to MAP


next do MAP to VSS using a pitot tube in the wind, then do MAP to RPM
using time as another input, than do MAP to o2...  just kidding
around obviously.

Thats a neet project and I must say a creative one.

The max frequency that the ECM listens to still limits the range of
the 3-bar you can translate though, doesn't it? I know that boost
translation might not really be the point of your
project.. I'm just boost minded.  my 0.02 good luck!