These Torque Cones create a venturi from the back pressure. The back pressure is increased at low speeds resulting in increased low RPM power and torque. At high speeds it increases exhaust velocity, which draws the gases down from the exhaust ports more rapidly, allowing your engine to perform more efficiently.; Smoothes out power curve, providing for more consistent performance Fits 1-3/4" stock and aftermarket exhaust Torque Cones are a must if you are running an exhaust without baffles Creates a venturi effect from the back pressure, increasing the exhaust flow