Is a 12 second, 20+mpg slant six possible?

Hey FABO ive got a 70 dart swinger with the /6 and and want to be able to do mid 12's or better in the quarter and get 20+ mpg without nos. Is this achievable or am I in dreamland? This will be a daily driver. Other option: 12 second 360 or better with decent mileage. Any help?