The right reply is this one -
xxx
All engines different types have different EGT rise during start.
First of all, where are the Tt probes - are they Tt5, Tt7, Tt9 ???
xxx
I have seen jet engines staying very cool and slow to get EGT rise...
The J-85 CJ-610 / Learjet 20s... looks like a hot start on every start.
EGT exceeds well above red line during start... by 150/200 degrees...
xxx
Happy contrails