Smallblock efficiency or How to have your cake and eat it too

so,, Im pleased with todays cruise results,,,148.9 km - 63.8km @115kph (72mph)and 84km @80kph (50mph) ...24.93 mpg imperial,,,20.7 mpg us... desktop dyno says the 340 makes 426 hp, just a number to put it in perspective. when i designed it i wanted 400 hp and 24 mpg...cake and eatin it too IMO..