[dmjlambert]

That is an interesting condition, runs fine cold but worse as it warms up. Has it done that for a long time or recently started it? Do you know if you have a hot slot intake manifold that heats up the carburetor? Since you have a lot of stock setup I just wonder if the problem could be related to boiling gasohol. Do you have the ability to try no ethanol gasoline on next fill up? I'm just throwing the idea out there, don't know how scientific it is. When you say ran fine for a while, do you mean until it warmed up, or for a few days?