Proves you suck at math. Even if you only get 1 mpg (which others have shown more) with an intake that 17 extra miles per tank. If you were geting 21 and are now getting 22 mpg your cost per mile at $4.15 a gallon is .197 and .188 respectively.
If you spend $60 on an intake it would take about 6500 miles to pay for itself. Thats not alot when the average driver drives 12,000 miles a year. I am more than average in that I drive 15,000 miles a year just to go to work and back. Its nothing for me to hit 20,000 miles a year.
Take that .009 difference and it will save $180 over that 20,000 miles, and thats only if yo see 1 mpg. If you get a more significant change in mpg, the savings raise substantially.
Quit talking out of your ass and let the people that know what they are talking about answer questions.