Anything can happen....take a look

[Wiseman]

Hammerhead , it's not so much about air speed , but more volume of air . Diesels rarely run at stoichiometric . Most of the time they run lean and respectively low EGT . When pushed hard there's barely enough air to provide proper combustion . The molecules of oxygen content in the air itself is what is getting in reaction with the fuel molecules. To make it easy to understand I'll say : given amount of hydrocarbons can get in reaction only with corresponding amount of oxygen . The excess oxygen and the rest of the gases in the air are heat carrier to outside of the combustion chamber . So here it comes: Not enough air - high EGT . To much air - very low EGT . To get the best efficiency of the engine is a matter of a fine balance between both and correct mapping of everything else . Very difficult task!!!
Unilevers , Gearhead and Rawze have gone a great distance researching and experimenting to find the best compromise for most every day use . On other hand you're on the extreme.
I think you need CM870 CPL8518 with HX-60 touched by one of this highly regarded guys.
Disregard what I think . It's just biased opinion.
People are saying: torque is needed to get rolling. Power is needed to keep it moving ones it gets to speed . With 1600-1800 rpm engine is in the power band to do what you need . The torque curves down to protect the engine from to much stress and rpm/power takes over .
The best place to put your pyro is just before the turbo so you have the exact temperature that hits the turbine . If I recall correctly anything above 1350-1400*F for more than 5 min will kill the turbo . The probe on the outside takes time and if fan is on , the readings is just a guess of what actually hits the turbine, cage and nozzle.
It's just my take on this pyro probe placement .