A spacer makes power solely based on fuel is no longer boiling over into your intake and the gasoline is burning more efficiently. A statement that it makes more power is partially false, but true. It only makes more power in comparison to not using one. Simply, because the gas is no longer boiling. It cools the fuel in the carburetor float bowl by simply acting as an insulator of heat. The fuel bowl is cooler, therefore the gasoline is not boiling in comparison to not using a spacer.
