Thanks for the advice.

The tuning could need a slight adjustment, but doesn't seem to be the major cause of the problem. The engine doesn't die in a climb but the line being too stiff sounds most likely. I did change out the tubing that came with the tank for that reason. I put in some that seemed more flexible to me. I haven't had any problems with it coming forward in the tank but perhaps it is still not flexible enough. Is there some kind of fuel line that is better than another and more flexible?

Thanks again,

J