Pyrometers/thermocouples are basically thermometers used to measure high temperatures. They are typically used by the turbo Regal community to measure the output temperature of the turbo and the inlet temperature at the throttle body. We used a Pyrometer back in late 80's and early 90's to compare the efficiency of the stock intercooler vs a front mount vs a liquid unit. The liquid intercooler containing ice water as its cooling medium was able to reduce the charge air temperature into the throttle body to a low of 72 degrees with an average temperature of approximately 80 degrees. If my memory serves me correctly the stock intercooler lowered the charge air temperature to approximately 150 degrees and the front mount reduced the temperature to approximately 115 degrees. I believe the ambient temperature was 85 degrees and boost was set at 21 #'s.