It may very well be vapor lock due to heat soak. Edelbrock/Carter carbs are prone to that because the float bowls are directly above the base and the intake. Heat soak is a real issue with the puppy pee gas we have now days. Non ethanol premium seems to help as well as high octane race gas. Carb base insulation helps as does a fuel return system. The guys that have installed a small pump near the tank with a momentary switch you use only as a primer pump probably works the best.