Intakes generally do improve MPG if they improve the the airflow and throttle response of the vehicle. But it stands to reason, and take no offense, the nut bolting the cold air intake to his/her car is not trying to conserve gasoline.
Intake + better foot control = more MPG.
Just like the Tesla Roadster, goes 125 miles on one charge, but drive it like a sports car is it only goes 30 miles.
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