Ford bronco 351 windsor v8 and chevy k5 blazer 350 v8 mpg?

i like both vehicles pretty much the same but i would like to know the mpg for both vehichles and what i could do to increase the mpg without decreasing horsepower. i am deciding which one to get this summer for the scool year. i live about 7 miles away from my school so i probably would commute around 16-18 miles 4 days out of the week.