I just ran across this data on the 2nd gen RX7 mass airflow sensor.
 Bosch wrote it up as part of the L jetronic injection system manual.
 I suspect it is made by Denso under license and installed
 in 1986 to 1991 RX7's. I don't think it is a computer.
 I think it is similar to a 555 system. All hardware and no
 software.

 Perry Mick has been flying this system for years in his Long EZ
 with hundreds of hours.

 It is very reliable. He has tricked the ECU into thinking it is
 still in  car. He has even installed an RX7 instrument panel
 in the cockpit.

 There are probably over 100,000
 of these systems out there. They are real cheap I suspect.

 Paul Lamar

 Paul,
 This may not be doable for Aviation and I have no doubt that someone will
 tell me why, however all ideas should be explored if only to eliminate
 them
 IMHO. Now some motorcycle carbs have floating slides whereby the density
 of
 the incoming air varies the slide compared to the throttle position - for
 altitude compensation. I can't remember exactly how this is accomplished
 by
 lifting the slide with the incoming air. There is a sloped face which is
 supposed to have a critical angle to accomplish this task. It may be there
 is a calibrated spring that air density is pushing against.

 This is the simplest solution air density adjustment I have heard about.
 For your consideration.
 George ( down under)


George,
My motorcyle has these. Tuned for sea level, it runs rich when going over
the Sierra's.
If you tune it for Denver, pings like crazy at sea level.....
The slide is lifted pulling the mixture needle out of the jet by the low
pressure area created by the air flowing by an orfice in the bottom of the
piston.
The top of the slide has a larger piston (or diaphram) and the vac on the
top side pulls the slide up. But they are not density sensitive.
Sorry.....
Larry


Sounds similar to SU carburetors..  In those, the mixture is enriched
by lowering the jet (or going to a smaller needle).  The choke on my
parent's old Volvo works by a cable connected to a lever which lowers
the jet.  Additionally the cable acts on a cam that rides against bell
crank on the throttle shaft to raise the idle speed.  It works ok, but
not great.

I still like the idea of being able to go to idle cutoff.  This system
doesn't support that.


Regards,

Matt-