I have a Dodge 2006 V6 2.7.I‘m thinking of getting a Flowmaster exhaust system and waswondering if you loose gas mileage with it.
No, you should see a very slight gain in mileage with a more free-flowing exhaust.
it shouldn't hurt it,all your doing is letting it breath better and letting the exhaust out faster,it will sound a lot better ,i doubt that it will give you that much of a gain on anything but it wont hurt it,it ill be louder though,good luck.
No, an engine is basically an air pump,its sucks air in and pumps it out. The more air you move the more efficient the engine is. You should see an increase.