I ordered a pair of thermocouples from Roy Szarafinski that are to be used for measuring cylinder head temperature. They will be paired with my Westach dual needle CHT gauge. To ensure that they were working properly, and to determine any deviation that might be present (in other words, to calibrate), I placed the probes into a calibrated oven and used a secondary calibrated instrument (Fluke 287) to measure the applied temperatures. The results were not what I expected, but without going into too much detail, Roy asked me to send the thermocouples back to him as he believes there may be a flaw in his manufacturing process. I have a complete report of my findings in my project library, so I’ll not post all of those details here.