MarkT:
Why not use a temperature sensor with linear output over the whole temperature range if you want
good accuracy?
Because i'd like to use a sensor that has a 1/8" NPT thread on it. And there seems to be not so many available options. Thats why i linked to the one i'd like to use. But i'm open for alternatives.
I've looked into the MAX31865 and searched if there are PT100RTD sensors with a 1/8" NPT thread. Seems that this might to the trick:
https://www.ebay.de/itm/EGT-Typ-K-1-8-NPT-Abgastemperatursensor-Temperatursensor-Sensor-Thermoelement/302827504552
(sry, link goes to ebay.de but i think for specs its okay)
Will this make things easier with the MAX31865 and the sensor linked above?