Now that I have an XCal 2 and an infared thermometer, I have checked my gauge on the dash. In the 97 it has always ran at half to 3/4, even more so when it is 105+ out.
on my dash 1/2 is 190 degrees. 3/4 is 208-210. I suspect that 210 is fine, it runs good, stays around there, didn't puke its guts on a recent road trip and idling around at 115+ ambient (IAT temp was 124).
As far as tranny temps, I think that you will find that most say that 175 is optimal, 220 is high and starts breaking down fluid and is the reason for 20-30k fluid changes, and 250 will start seals hardening and breaking down.
If you really wanted to be good to your tranny, add an external cooler after the radiator heat exchanger. I don't know where you live, California or someplace North of the border, but I left the radiator in line even though it is aways relatively warm where I live.
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