I have built pipe burners for years. In my black smoker I have 2 , 1 1/2 inch burners , 65 inches long, 65K btu. They have a cross tube allowing each burner to light the other burner. The smoker also has a 1 inch burner the same lenght for the smothered wood box. All of the burners have a mixer, valve, orfice and extension for air/fuel to mix before the first slot.
Chas