If your mopar is you daily driver!

i meant thermostat temp. i always thought, the cooler engine temp makes more power, but more wear, hotter temp reduces wear and cleaner exhaust gas, how would either effect mpg? the only thing i ever worried about was all the power i could get and keep it cool on the street.
what about the intake heat crossover. any effect on mpg? they have pissed me off in the past so if its easy enough, i block it off.