It is very important that the starting EGT temperature be consistant as well when trying to determine what "effect" a jet change has made to a tume up. A quarter second more on the two step can cause the inital egt reading to be 50 degrees hotter then the run before with no change in jet or weather. This will level out when approaching peak temp near the end of the run, but you may still see a 10 degree hotter peak temp eventhough you changed nothing.
EGT have there place, but this is where an Air/Fuel sensor proves superior!
