Daily Driver.. LA318 vs 360 Magnum

for mpg you need good gears, a good tune, light weight and aerodynamics! but theres more mpg in how it driven than anything else! drive it like it ant got brakes and ya got an egg for a throttle peddle! we tried it all searching for better mpg in trucking. we were averaging 4.5 mpg in the 80s and theres trucks getting 7.5 average now but thay dont run as fast or pull near as hard on a hill...