Sonex Electric Instrument Installation Instructions - Manual (Page 3)

4. Fuel Flow Option: There are two Fuel Flow meters that we have used with
our electronic instruments. A metal “Flo-Scan” unit and a Plastic Unit. See
images below. Sonex recommends that you use the Metal Floscan Unit shown
below.
Metal Floscan Fuel Flow Unit Plastic Fuel Flow Unit
The Metal Floscan Fuel Flow Installation Instructions can be downloaded from
the Stratomaster or Sonex Web Sites.
The FF sender instructions are relevant to the “Smart Single” Stratomaster FLT-II
Installation. The supplied resistor should be installed between the FLT-II brown
(+5v) wire and the Floscan signal wire, with the Floscan red wire connected to a
12v source.
The plastic unit comes with 4 different jets plastic washer that will be installed on
the inlet side of the unit. These washers restricts the amount of fuel that can flow
through the meter and directs the fuel stream for consistent readings. We
recommend using the 3mm Jet (845) inner diameter (allows over 13.6 gph and
still yields consistent fuel flow readings).
FYI: The recommended “K Factors” for this unit are:
3500 with restrictor jet installed and 1330 with no restrictor installed. Follow the
calibration instructions in the manual to figure out the correct “K factor” Setting for
your unit.
5. Tachometer Set-up: We have set up our tachometer to take a reading off of
one of the “pigtails” exiting the Alternator Stator. We accomplish this by simply
running a wire splice from the pigtail to the “Rev Counter” terminal on the electric
instrument. Only one of the two pigtail wires will give you a reading. If you don’t
get a reading from the first one, try the other one.
The 10-Amp Alternators used on the 2200 Jabiru and 2180 Aero Vee yield 5
pulses per revolution, so the Rev Setup on the Stratomaster Units will be 50. If
you’re using the Grand Rapids EIS, the “EMP” setting will be 5.
The 20-Amp Alternator used on the 3300 Jabiru yields 6 pulses per revolution, so
the Rev Setup on the Stratomaster Units will be 60. . If you’re using the Grand
Rapids EIS, the “EMP” setting will be 6.
As an alternative on the AeroVee Engine, you may put a splice in the “p-lead” of
your primary magentron ignition unit. This will yield 2 pulses per revolution, so
your Rev Setup on the Stratomaster Units will be 20. (EMP=2 for EIS Units)