I have found that if you do not have at least 1/4 inch ( 6mm) in the flow, you are not getting a true reading. I can run my BMT with the probe about 1/8 in (3mm) in the exhaust flow and lower the egt by 200 deg. I checked the EGT with a seperate Digital pyrometer and the true temp was measured with the probe at least 1/4 inch in. At least this is true with the BMT.
I ran Ram engines a long time ago and I know that the EGT was much higher than the ECU displayed. Once again I checked the EGT with the pyrometer. In my opinion, you are "fooling" the ECU into seeing a lower EGT if you have only a small length of the probe inserted. BTW, I am in no way bashing the RAM or anyones engines or electronics.

Maybe Andre at BMT will chime in


Mickey
A-1 Hobby