Tony,
I wonder if the rig had these problems BEFORE the installation of the new carb. I don't generally spread bad press, but the foreman at work installed a Edelbrock Performer (?) carb on his new 350 and had funky hot start problems also.
If you don't have to choke the carburetor when the rig is first started in the morning, it might indicate too much fuel from the git go!
Inkys vapor lock suggestion might be right on the money!
If this is a flooding problem, you should see evidence of it out the tailpipe, or hear the engine blubbering after it does start.
Experiment...next times it does it, either clear the carb the way I described above, OR, pump the hell out of it. It will react to one of these attempts.
Stuart
