ok i understand the thermastat controls the temp. but i still dont understand. aluminum disperses heat better correct? so why wouldnt the radiator cool better, wouldnt it take longer to heat up and cool down faster? it claims to give you a 20% cooler system, so why wouldnt it be better? they make engine blocks out aluminum because of there abilty to cool faster, right? these are just random question i have, just trying to get it straight.

99 wrangler sport, auto. 2.5 inch lift, 31 MTR's