I have two MAP ports on the rear of my intake plenum that feed the EC-2.
I am taking the pressure from this third port at the bottom of the manifold to
the regulator. I have a vacuum gage…I guess I should check the steadiness
and consistency of all three ports.
Bill
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Al Gietzen
Sent: Tuesday, June 10, 2008 9:26
PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Sensors
Perhaps
I should add that the original line from the sensing ports to the pressure
regulator was quite short; maybe 10”; so there was very little damping
there.
My fuel pressure regulator (Airmotive) is getting its
MAP from the two small (1/8 “) tubes that lay in the primary ports on the
Renesis…Are you saying that I should move this pressure reference to
someplace else? You say you know it is not good…How do you know
this?
Bill B
Bill;
I
was measuring fuel pressure to the fuel rails to verify the EM2 calibration.
The needle on the gauge was swinging very rapidly from about 20 to 40. I
don’t recall what RPM, but I guess near idle. Perhaps stating that
“it is not good” is an overstatement, and perhaps it just happened
that the pressure pulses hit a resonance in the gauge; but my judgment was that
it could affect the engine operation and could be damaging to something else
long term. I had already put damping in MAP line to the EC2, so I decided
to T it into that line, and the pressure pulsing went away.
I
have a 3-barrel TWM TB on a short intake manifold. The MAP sensing ports
are just downstream of the throttle plates.
Al