Red Headed Stepchild-75 Swinger LSX Swap

5.7 hemi said

Just asking......why is there 2 exhaust pipes exiting the fenders?

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The larger 3" one is the downpipe from the turbos. Which would be your normal exhaust gasses after going through the turbo, much like it would be coming through a Manifold or header. But because of the turbo there, it will be much quieter than your normal open header exhaust under normal driving conditions, while not In positive pressure(boost).

The smaller one is a 2" piece from the wastegates down. Basically when the wastegates open at whatever spring pressure(partial positive throttle/boost) or wide open throttle (whatever your external wastegate spring is)it will dump that exhaust straight out(much louder). Which is essentially straight header volume, and much louder than the muffled sound of the normal 3" exhaust because it never goes through the turbo because the wastegate is. Bleeding off that extra pressure so you don't build too much boost. Some recirculate their wastegates into their exhuast to keep things quieter when they get into boost but I personally love the sound of an open wastegate car.