LSx Valiant Build. Take a look inside...

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Those are what you're running? I thought they were turbo headers? I know of a guy running them.
They are turbo manifolds, not just standard exhaust manifolds. With them flipped it avoids the steering gear box clearance issue and will run down on one side and connect to the turbo on the other side. This is them on his Carb'd foxbody he calls Chevystang. Pulls the front wheels every time, and runs low 9's.