For my Jeep, I need to replace the thermostat housing. I've tried a few different thermostats, not sure I've seen much of a difference. With our extreme heat, it runs a bit warm. While the housing is off, now would be the time I can replace the thermostat. It's currently got a 180* High-Flow Murray (Murray is OEM manufacturer). I also have a 195* OEM Murray (I bought from the dealer) and a 195* High-Flow Murray. So my question is, which do you think would provide better cooling in extreme conditions? The reason I wonder is with a wider opening, this means the coolant might flow faster which would mean less time in the radiator to cool down. But I see it also as maybe being beneficial, less time in the engine getting hot.