just ran this engine for the first time last weekend and it ran awesome the whole weekend very happy and comfident with this engine. I ran it with 7mm venturi and ae 2035 pipe got 8mins runtime, the engine isnt even close to broke in and it was running really fat so i was impressed with that, also has anyone done any testing on this engine with different pipes, maybe you guys can save me the trouble, what have you found works best?