Just wanted to throw in a comment here. It has been too cold here for me to test XJET's information about using smaller holes in the exhaust nipple to maintain tank pressure. I too have seen air bubbles in the line during transition. Since the engine I am working with is a front needle carb, the bubbles are likely coming from an improperly pressurized tank. I just want to make sure everyone doesn't drill out these nipples, until we see what effect a smaller hole has on keeping the tank from depressurizing. XJET's comments make a lot of sense to me. Good luck Guy's!

Andy