Do flowmasters improve gas mileage

[Laddy]

I heard flowmasters give you 3-4 more mpg? Is this true?

 

[terdrocket]

No, only magnaflow.





Nah, aftermarket (bigger outlet piping) exhaust should free up some hp, allowing you to accelerate the same using less pedal. However, 1 mpg maybe and thats if you can keep out of the gas and resist feeling the improvement and hearing the sound.

 

[F14CRAZY]

It technically would because of less resistance, but as said before, only residual.

 

[aldive]

I heard flowmasters give you 3-4 more mpg? Is this true?

If you combine the new muffler with a cat back pipe system as well as a free flowing intake, the mileage increase is indeed possible.

 

[huskyfan23]

I'd say maybe 1mpg max. Driving habit, weather and environment depend mostly on your mileage.