I went up today for a few laps at 3000 over Paine Field. The engine ran well
 below the staging point, but started stumbling when above the staging point. It
 ran smoothly through the staging transition on the ground, but when in the air I
 could not tell by the mixture monitor if it was lean or rich. I tried leaning it
 out and richening it up, but results were inconclusive so I stayed below the
 staging point for the remainder of the flight. I'll tune it in flight when I can
 get higher.  Temps were down around 130 degrees at 4800 RPM and 110 mph, MP was
 not noted.

 I accidentally hit the cold start switch while on downwind with two other planes
 ahead of me, and  the tower told me to go around on final with the engine
 stumbling badly, but the plane ahead turned off onto the taxiway just in time so
 I told the tower that I would really like to land, so they cleared me.I still
 had 7000 feet of runway ahead of me.  The engine died as I turned off onto the
 taxiway and then I noticed the cold start switch. The first order of business
 was making and installing a switch guard for the cold start switch. I'm also
 going to pre-load the switch with a rubber band so it stays in the off position
 unless I'm pushing it on, and can just pull the rubber band off of it if I need
 to shut down a set of injectors and run the remaining injectors on cold
 start.(limp home mode for failed injector.)

 The fuel self transferring issue was resolved by installing manual valve on the
 transfer line between the tanks.



 Brian Trubee

 Dave Leonard had an off airport landing because of that cold start switch.
 One can get a flip up guard that covers the switch to prevent inadvertent
 operation.

 "The fuel self transferring issue was resolved by installing manual valve on the
 transfer line between the tanks."

 Are you sure about that Brian?
 Did you notice the fuel pressure when the engine starting running rough?
 Could be you sealed the right tank when you closed the transfer valve.
 I suspect the right tank vent is not working.

 Paul Lamar



 The right tank vent is working- I put a piece of tubing over the tank vent,
 opened up the tank fill, put my ear to it and blew into the tubing- heard the
 air going into the tank.

 But yes- I didn't check the fuel pressure at the staging point, that's a good
 point, and it's on my to-do list.

 Also- to everyone out there running the EM2- what do you have for calibration
 settings for your manifold pressure- what values do you have for scale factor,
 low end offset, etc? I screwed around with mine and need to get it back to where
 it should be. Between all those variables, I'm having a hard time figuring out
 what all these values are supposed to be.


 Any help here would be appreciated.

 Brian Trubee

                        

Brian

The map data that i finally wound up with after 250 hrs is on the attachment.

John Prendergast

Got any pictures of your intake plenum John?
Where is the pressure tap located in that plenum?

Paul Lamar