When you say a minute do you mean simply momentarily or actually a minute? I am by no means an expert but have had simular problems.As stated above you dont want the clunk to fall forward because it will pinch the line and you will starve it anyway.When in a dive you will not be applying power(I hope) therefore the engine will continue to run even though the clunk may not be covered with fuel.If you are acually talking about a minute or close to it nose down under power it will starve itself in my experiece.