What you're really after as an operator is the fuel pressure with respect to the airbox: See page 7-39 of the latest version of the SV Installation manual, excerpted below:
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Rotax 914 Differential Fuel Pressure Sensor
The fuel pressure sensors that Dynon Avionics sells are not suitable for use with the Rotax 914 engine, as Rotax specifies that fuel pressure on the 914 engine be measured with respect to the air box pressure. All fuel pressure sensors sold by Dynon Avionics are only capable of measuring fuel pressure against ambient air pressure.
The UMA N1EU007D sensor is a third-party differential pressure sensor which measures fuel pressure with respect to air box pressure as required by the 914 engine. This sensor is not supplied by Dynon Avionics, but it is supported by SkyView.
Install the differential fuel pressure sender in an area convenient to the connections on the engine. The mounting threads are 5/8-18. Connect side of sender marked with a “W” to the fuel line close to the carburetors. Use 1/8-27 pipe thread fitting. Connect the other side of sender to the air box. This can be done by inserting a “T” in the carb vent lines that go to the air box. Use a 1/8-27 pipe thread, barbed insert into the sender. Make sure all fittings on the air box lines are tight using spring clamps or tie wraps.
SV-EMS-220/221 Installation and Configuration
7-40 SkyView System Installation Guide - Revision P
Connect the red wire to EMS pin 15 (12V power). Connect the black wire to ground (an SV-EMS-220/221 ground is appropriate). Connect the white wire to any of the “C” type inputs on the SV-EMS-220/221 module - pins 8, 22, or 31 only.
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If you're after the airbox pressure with respect to ambient, you can fit any of our Kavlico pressure sensors to easily get air box pressure (gauge pressure). I'm not sure what the boost profile is for the 912, but you'd probably want either the 5 or 15 PSI sensor.