I am looking to build a small (very small) wireless transmitter using a thermistor that will operate inside of a running combustion engine in order to measure piston or connecting rod temps. I have done this by making a long and painful drilling continuously through the crankshaft and then mounting the telemetry in the open air mounted in the crank pulley.
However, sometimes I want a single reading off a piston in the middle of the engine, thus a small single channel device. I have run chips successfully up to their 250 F limit (and a little beyond), but then this requires special oil cooling and creates bias in the measurement usually. Are their any chips that will function even briefly at 400 F in a heavy, hot, dirty oil bath... and while whirrling around or oscillating rapidly?
I am familiar with PIC chips... but am no computer scientist.
Thanks, Matt