Can't make an educated guess from the data given but here's a few
questions & comments.

Can you clarify what you mean by "precipitous power drop"?  Does the
power go down at higher MP?  (6100 at 22.6" aint bad on a FP prop. What was the airspeed & altitude?  EVERYTHING MATTERS!)

Is the EGT imbalance only at high power?  Are you sure it's not
instrumentation error?

As Ed asked, what was the result of varying the mixture control at
high power? You say that engine is silky smooth below 6100.  Does that imply it is
rough above 6100?

The % power readout of the EM2 is meaningless if the fuel flow
function isn't calibrated and you haven't plugged in a realistic value
for your engine's max power.

Tracy


On Sun, Feb 5, 2012 at 10:01 PM, <bktrub@aol.com
<mailto:bktrub@aol.com>> wrote:

    I've got just over 20 hours on my plane today, all of the lower-
    end bugs have been worked out. Right now I'm having power drop off
    precipitously right at 6100 rpm- 22.6 inches of MP and around 70%
    power according to the EM2. This is around 130-140 mph IAS. The
    fuel injection Map shows a smooth graph at that point. I thought
    that there might be a timing issue so I tried advancing the timing
    about 2 degrees but that did not change a thing so I set the
    timing back where it was previously. I am seeing about a 180 f
    difference on the two rotors- I went to mode four to try to
    balance out the egts, but I could only effect about a 20 degree
    change. Rotor 2 consistently shows somewhere above 1800 F, which I
    tend to question. I'll re-check my calibration.   I have had the
    injectors cleaned and tested so unless one of them got clogged,
    that should not be an issue. Still, I should pull them and have
    them re-checked. I may have an issue with the EGT probes themselves.
          Down below 6100 rpm the engine is smooth as silk, but obviously
    there is an issue above that .
              Brian Trubee
    RV-4  13 BREW