The really interesting part of this test is that even my 'tough' EGT probe not only responds as quickly, reads the same accuracy as the 'fast acting air temp sensor' but its far superior when you see any transient happen. though It's obviously a much dampened version of the fine wire but it still shits on the ACT

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The other thing about the ACT is just how long it takes to return to start temp and I am not talking about the brass body being elevated to the measured temp either since the test is heated from ambient for only 6 seconds, its ~4 X my production spec EGT probe in time to return back to the start temperature, really bad! I guess the plastic vented shroud acts as an insulator? dunno don't really care

the dynamics of air flow inside a manifold dampen allot of what you see in these types of bench tests where the air flow rates are but a small fraction, so what seems like a crazy difference here is not so much in an engine environment.