1.      EGT’s are 2000-2050F.  Seems a tad high to me!!  My EGT probes are located about 2.5” from the rotor housing.  When I shut it down my exhaust manifold/muffler was a very nice glowing red.  It’s made out of Inconel and is .06 thick so it seems to hold up pretty well.  But if it’s like this at 1600RPM what’s it going to be at 5800RPM??

 

As others have noted; something definitely amiss with the EGTs.  My EGT probe placement is the same as yours.  I looked for recorded data points at idle conditions in my data, but since this is not an area of interest could only find a couple, and conditions probably different than yours.  No load at 1600 showed EGT of 950-1000.  With a prop I’d guess something more in the 1100-1200F range as normal.

 

On my 20B from Atkins the timing marks on the pulley were not correct; probably because of a change to a 12A front cover with different pointer position.  With some effort, we learned that the timing was about 23 degrees too late.  Looking back at the data it seems that caused an increase in the EGT by maybe 200-300 degrees.  So I’m going to guess that even a serious timing error would not explain your results.

 

The deep red glow would suggest something too high; maybe 1500-1700F or so; 2000 would be getting quite bright.  Of course how it appeared depends on how light it was in your shop.

 

Also guessing; the mixture so far off as to cause that high a temp would result in rough running of the engine.  It suggests you need to look at mixture (you have O2 sensor?), timing, and EGT calibration.  Call Dave and get his input on trouble shooting.

 

MAP reading seems low.  Probably 11-12” Hg would be more typical.

 

FWIW,

 

Al