the idea that backpressure is necessary for performance/torque/whatever is a total myth. Maybe back when the dinosaurs roamed, you needed backpressure for some pushrod behemoth, but nowadays, the less backpressure the better. period. the whole point of a smooth mandrel bent straight through exhaust is to speed the exhaust gasses and evacuate them as fast as possible. Sound like backpressure to you? No. The reason you don't want a huge 3" exhaust on a N/a car is because its actually slower unless forced out by a trubine. But in either scenario, the whole point is to reduce backpressure and speed exhaust gas evacuation.

sorry:blah: h: