I need it all up top. Don't care about down bottom. I have the southern express on my animal and it rips. It is the most expensive but if you want to be up front that's what it takes. I am new to the clones and really don't know what pipe would work best for my situation. Btw I do not build my own motors
From all of my testing it has shown gains. Not that I am saying it gave the engine 2hp but what it did was broaden the torque cure higher in the RPM range.