Edelbrock Thunder Series Adjsutment

I have a 340 newly rebuilt with a hot restart problem. It appears to be vapor locking. What could be the cause? The carb,fuel pump,ignition system are all new.
Thanks

You need a heat spacer. Try "googling: carb heat spacer

Here's one search: http://www.jegs.com/c/Carburetor-Spacers/10289/10002/-1