TerryTucker,
What carburetor are you using?
I now have a Holley two barrel AA-1 carb on my 261 that frosts and then condenses water, until the engine heats up. I am lucky that the engine runs fine even at start-up. There is no insulator under the carb and the original intake is heated with heat tubes from the Fenton headers.
I agree with carbking as to my situation - too much carb (or, at least too rich a carb). I have adjustable jets, so I am playing with the settings.
I have run 700 miles with the carb this summer. The Suburban runs smooth as silk, with plenty of power (15 MPG at 60-65mph).
