I've got a 300hp crate 360 magnum in my 91 power ram 150 4x4 short bed truck, I'm running a Napa premium 195 thermostat, a 3 row brass/copper radiator, 5 blade mopar viscous fan. I never have any over heating issues, the hottest this engine has ever got was 230 while I was working it real hard climbing in 4wd.
I'm running an aluminum dual plane mopar m1 intake and a quick fuel super street series 680cfm vacuum secondary carb. I've been told I would have a little more power if I switched to a 180 degree t-stat because the intake will be a little cooler.
It's only about a 30 minute job to swap t-stats, and I can get a 180 t-stat and gasket for about 10 bucks, would it be worth trying? I'm not to concerned about fuel mileage, but my heater is pretty important in the winter months. But I've never ran anything but a 195 t-stat and if there is a little more power to be had by going with a 180 then 10 bucks and 30 minutes worth of labor seems worth it to me.