Hey everyone, well i own a Z and a Mazda 6, and i know that my question for my mazda will be answered better here because no one does true duals for it on the mazda forum. So my question is this, the car is naturally aspirated v6, and i am getting new headers for it, and want to do a 2 - 2.25" true dual system all the way. No cats, 2 resonators, but i want to know if it would pose a problem to use mufflers with 2.5" inlets. will it ruin the necessary backpressure that i need, or does it not matter since its at the end of the exhaust track.

 

If you were running a 1,000 HP race car, I would be concerned with a perfect exhaust system size match, and scavenging. But for a street car I see no problem.