I think you are over-thinking this one. I removed a Behr and installed a Wahler, both were marked 87*C. I then tried a Beck/Arnley "french" t-stat marked 80*C all in an attempt to get the gauge to read cooler, it is always at a needle-width below 100*C.... The result is, tada! Nothing! The temp is exactly the same, maybe a needle width cooler, but nowhere near 80*C, winter, summer, hills, traffic, highway, etc. Seems the guage isn't as accurate at it should be. The moral of the story is that a thermostat either works or it doesn't and it really doesn't matter who made the bloody thing. Install a new t-stat, burp the system, keep an eye on the gauges and drive happy. RT

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