I had to go to the SF valley to check out a laser jet tube cutter
and MM welder and stopped off at a Pick a Part junkyard.

I found this GM LS1 mass airflow sensor for $45.
Retails for $399.95.
Took me five minutes to get it out of the wrecked Isusu truck.
All it took was 2 screw drivers a phillips and a straight :)

"Mass air induction systems measure airflow with an electronic "hot-wire"
type mass airflow sensor. The sensing element in the air intake provides an
output voltage reading that is directly proportional to the amount of air
that is entering the engine. This airflow measurement reduces the
calculations required to control fuel and ignition spark advance. Mass
airflow sensors can react quickly and accurately to sudden changes in
airflow."

Usually it is 0 to 5 volts. I will use this with the Arduino program
and a slide throttle on the RV4.

They are easy to locate and mount as you put them upstream from
the slide throttle in 2.75 inch ID hose.

Paul Lamar