Posted for "cgalley" <cgalley@qcbc.org>:

 Those numbers without qualifiers do not mean much.      Are they under
 standard atmospheric conditions at Sea Level?  How far from the exhaust
 flange is the probe installed?  EGT temperatures are very important but
 seldom are absolute. These relative temperatures are useful in determining
 power settings for a particular set of atmospheric conditions. They are also
 useful for checking spark plugs and mag workings.  Cylinder head temps on
 the other hand are closer to being absolute temps and controlling these
 temps will determine the long term health of the engine. The CHT that
 Continental lists as red line for their engines will destroy them in short
 order.  Most of the Bonanza people like to keep their CHT at or below 380°
F.  This is a much more critical temperature.
 
 
 If you are talking about Walter Atkinson, I know he has run the TSIO 550 in
 a instrumented test cell at Ada. This test cell is better than anything that
 Continental has. The only reason that GAMI exists is the lack of good
 operational data from Mobile.