Air flow & such

[George M. Dailey]

First off, I think you would have to know how the flapper system calculates
or estimates mass air flow. Probably a function of flapper position and
inlet air temp. The next step might be to establish a flapper position
voltage and inlet air temp voltage for a given MAF voltage. This could be
easily done with a data logger and a flapper and MAF sensor mounted in
series while driving the car. Once you've estabilished this relationship
over the operating range of the engine, you simply build a "black box" to
convert the MAFs frequency or voltage output to the equivelent flapper
position and inlet air temp (voltage,curent, or resistance) that the ECM
expects to see. There are a few blow flies in the oil though. 

If you don't know how the flapper system calculates or estimates mass air
flow, there could be problems. Coolant temp might be factored in for example.  

A simpler solution might be to use a MAF system off of an exiesting OEM MAF
equiped engine of the same # of cylinders and approximat displacement.

Good luck,
GMD

At 10:20 AM 11/20/96 UTC-2, you wrote:
>  I have wanted to get rid of the restrictive 
>> flapper type in favor of the hot wire or film type ..
>...Hi! I also want to get rid of that flapper: ... the problem I guess is
to get the signals matched, and the 
>problem with THAT is that the flapper has a weird change in 
>resistance as you sweep across. ...
>As far as I know, the flapper initially overshoots a bit, which acts 
>as a sort of acceleration enrichment. But its wide open from about 3-
>3500 rpm, anyway.
>
>Anybody?
>
>Sincere;y
>Andrew
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>Dr A. N. Bosch
>Physiology Department/ Sports Science Institute
>University of Cape Town Medical School
>P. O. Box 115
>Newlands 7700
>South Africa
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