All good points so I thank you for your reply. I have decided to try venting the tank through the bottom of the fuse and go from there. If I get the feeling that pressurizing the tank may have benefits I am going to try installing a pressure fitting on the muffler. It has all boiled down to experimentation and performance for me I guess so I will start with the least intrusive action and go from there. I don't think I will buy another engine that involves venting to the atmosphere though. I got surprised by this purchase and actually favor the pressurized tank. Thanks again.