The only real problem I had was that the O2 reading in the EM-2 seems erratic.  Todd, did you ever figure this out?  Mine was so wishy washy that I couldn't confirm whether a longer "bar" means richer, or leaner.  I swear sometimes it would go one way, and some times the other.  Finally, it just went to no bar, and stayed that way.  I can't say that I can blame the EM-2, since my old meter did the exact same thing once.  It just refused to work one day, then worked fine the next.  Maybe everything will just work perfectly tomorrow, and all will be well.  I have to admit to being tempted to take the FJO wideband O2 meter out of the RX-7 for use in the plane.  That would be sweet.  Fast, reliable air fuel reading from 10 to 20. 

Rusty;

I had the same problems during the dyno runs with the O2 sensor and monitor I got from Tracy.  Replaced the O2 sensor with a heated sensor (three lead) they had at the dyno connected to their computer readout and everything worked fine.  I wasn’t sure if it was the sensor or the monitor but I guessed it was the sensor.  My O2 sensor is installed in a custom muffler about 18” downstream from the manifold.  Haven’t tried a new sensor with the EM2 yet.  Where did you place the O2 sensor?

Al